diff --git a/itchat/__init__.py b/itchat/__init__.py
index 256fc721..be1e467b 100644
--- a/itchat/__init__.py
+++ b/itchat/__init__.py
@@ -7,8 +7,8 @@
 
 instanceList = []
 
-def new_instance():
-    newInstance = Core()
+def new_instance(proxies=None, userAgent=None):
+    newInstance = Core(proxies=proxies, userAgent=userAgent)
     instanceList.append(newInstance)
     return newInstance
 
diff --git a/itchat/components/__init__.py b/itchat/components/__init__.py
index f088c173..88886396 100644
--- a/itchat/components/__init__.py
+++ b/itchat/components/__init__.py
@@ -3,8 +3,10 @@
 from .login import load_login
 from .messages import load_messages
 from .register import load_register
+from .request import load_request
 
 def load_components(core):
+    load_request(core)
     load_contact(core)
     load_hotreload(core)
     load_login(core)
diff --git a/itchat/components/contact.py b/itchat/components/contact.py
index 3ae3c02a..2d7e5d40 100644
--- a/itchat/components/contact.py
+++ b/itchat/components/contact.py
@@ -31,15 +31,14 @@ def update_chatroom(self, userName, detailedMember=False):
     url = '%s/webwxbatchgetcontact?type=ex&r=%s' % (
         self.loginInfo['url'], int(time.time()))
     headers = {
-        'ContentType': 'application/json; charset=UTF-8',
-        'User-Agent' : config.USER_AGENT }
+        'ContentType': 'application/json; charset=UTF-8', }
     data = {
         'BaseRequest': self.loginInfo['BaseRequest'],
         'Count': len(userName),
         'List': [{
             'UserName': u,
             'ChatRoomId': '', } for u in userName], }
-    chatroomList = json.loads(self.s.post(url, data=json.dumps(data), headers=headers
+    chatroomList = json.loads(self.post_raw(url=url, data=json.dumps(data), headers=headers
             ).content.decode('utf8', 'replace')).get('ContactList')
     if not chatroomList:
         return ReturnValue({'BaseResponse': {
@@ -51,8 +50,7 @@ def get_detailed_member_info(encryChatroomId, memberList):
             url = '%s/webwxbatchgetcontact?type=ex&r=%s' % (
                 self.loginInfo['url'], int(time.time()))
             headers = {
-                'ContentType': 'application/json; charset=UTF-8',
-                'User-Agent' : config.USER_AGENT, }
+                'ContentType': 'application/json; charset=UTF-8', }
             data = {
                 'BaseRequest': self.loginInfo['BaseRequest'],
                 'Count': len(memberList),
@@ -60,7 +58,7 @@ def get_detailed_member_info(encryChatroomId, memberList):
                     'UserName': member['UserName'],
                     'EncryChatRoomId': encryChatroomId} \
                         for member in memberList], }
-            return json.loads(self.s.post(url, data=json.dumps(data), headers=headers
+            return json.loads(self.post_raw(url=url, data=json.dumps(data), headers=headers
                     ).content.decode('utf8', 'replace'))['ContactList']
         MAX_GET_NUMBER = 50
         for chatroom in chatroomList:
@@ -81,15 +79,14 @@ def update_friend(self, userName):
     url = '%s/webwxbatchgetcontact?type=ex&r=%s' % (
         self.loginInfo['url'], int(time.time()))
     headers = {
-        'ContentType': 'application/json; charset=UTF-8',
-        'User-Agent' : config.USER_AGENT }
+        'ContentType': 'application/json; charset=UTF-8', }
     data = {
         'BaseRequest': self.loginInfo['BaseRequest'],
         'Count': len(userName),
         'List': [{
             'UserName': u,
             'EncryChatRoomId': '', } for u in userName], }
-    friendList = json.loads(self.s.post(url, data=json.dumps(data), headers=headers
+    friendList = json.loads(self.post_raw(url=url, data=json.dumps(data), headers=headers
             ).content.decode('utf8', 'replace')).get('ContactList')
 
     update_local_friends(self, friendList)
@@ -267,11 +264,8 @@ def get_contact(self, update=False):
     def _get_contact(seq=0):
         url = '%s/webwxgetcontact?r=%s&seq=%s&skey=%s' % (self.loginInfo['url'],
             int(time.time()), seq, self.loginInfo['skey'])
-        headers = {
-            'ContentType': 'application/json; charset=UTF-8',
-            'User-Agent' : config.USER_AGENT, }
         try:
-            r = self.s.get(url, headers=headers)
+            r = self.get_raw(url=url)
         except:
             logger.info('Failed to fetch contact, that may because of the amount of your chatrooms')
             for chatroom in self.get_chatrooms():
@@ -330,9 +324,7 @@ def set_alias(self, userName, alias):
         'CmdId'       : 2,
         'RemarkName'  : alias,
         'BaseRequest' : self.loginInfo['BaseRequest'], }
-    headers = { 'User-Agent' : config.USER_AGENT }
-    r = self.s.post(url, json.dumps(data, ensure_ascii=False).encode('utf8'),
-        headers=headers)
+    r = self.post_raw(url=url, data=json.dumps(data, ensure_ascii=False).encode('utf8'))
     r = ReturnValue(rawResponse=r)
     if r:
         oldFriendInfo['RemarkName'] = alias
@@ -346,8 +338,7 @@ def set_pinned(self, userName, isPinned=True):
         'CmdId'       : 3,
         'OP'          : int(isPinned),
         'BaseRequest' : self.loginInfo['BaseRequest'], }
-    headers = { 'User-Agent' : config.USER_AGENT }
-    r = self.s.post(url, json=data, headers=headers)
+    r = self.post_raw(url=url, json=data)
     return ReturnValue(rawResponse=r)
 
 def add_friend(self, userName, status=2, verifyContent='', autoUpdate=True):
@@ -369,9 +360,8 @@ def add_friend(self, userName, status=2, verifyContent='', autoUpdate=True):
         'SceneList': [33],
         'skey': self.loginInfo['skey'], }
     headers = {
-        'ContentType': 'application/json; charset=UTF-8',
-        'User-Agent' : config.USER_AGENT }
-    r = self.s.post(url, headers=headers,
+        'ContentType': 'application/json; charset=UTF-8', }
+    r = self.post_raw(url=url, headers=headers,
         data=json.dumps(data, ensure_ascii=False).encode('utf8', 'replace'))
     if autoUpdate:
         self.update_friend(userName)
@@ -406,8 +396,7 @@ def get_head_img(self, userName=None, chatroomUserName=None, picDir=None):
             if 'EncryChatRoomId' in chatroom:
                 params['chatroomid'] = chatroom['EncryChatRoomId']
             params['chatroomid'] =  params.get('chatroomid') or chatroom['UserName']
-    headers = { 'User-Agent' : config.USER_AGENT }
-    r = self.s.get(url, params=params, stream=True, headers=headers)
+    r = self.get_raw(url=url, params=params, stream=True)
     tempStorage = io.BytesIO()
     for block in r.iter_content(1024):
         tempStorage.write(block)
@@ -430,9 +419,8 @@ def create_chatroom(self, memberList, topic=''):
         'MemberList': [{'UserName': member['UserName']} for member in memberList],
         'Topic': topic, }
     headers = {
-        'content-type': 'application/json; charset=UTF-8',
-        'User-Agent' : config.USER_AGENT }
-    r = self.s.post(url, headers=headers,
+        'content-type': 'application/json; charset=UTF-8', }
+    r = self.post_raw(url=url, headers=headers,
         data=json.dumps(data, ensure_ascii=False).encode('utf8', 'ignore'))
     return ReturnValue(rawResponse=r)
 
@@ -444,9 +432,8 @@ def set_chatroom_name(self, chatroomUserName, name):
         'ChatRoomName': chatroomUserName,
         'NewTopic': name, }
     headers = {
-        'content-type': 'application/json; charset=UTF-8',
-        'User-Agent' : config.USER_AGENT }
-    r = self.s.post(url, headers=headers,
+        'content-type': 'application/json; charset=UTF-8', }
+    r = self.post_raw(url=url, headers=headers,
         data=json.dumps(data, ensure_ascii=False).encode('utf8', 'ignore'))
     return ReturnValue(rawResponse=r)
 
@@ -458,9 +445,8 @@ def delete_member_from_chatroom(self, chatroomUserName, memberList):
         'ChatRoomName': chatroomUserName,
         'DelMemberList': ','.join([member['UserName'] for member in memberList]), }
     headers = {
-        'content-type': 'application/json; charset=UTF-8',
-        'User-Agent' : config.USER_AGENT}
-    r = self.s.post(url, data=json.dumps(data),headers=headers)
+        'content-type': 'application/json; charset=UTF-8', }
+    r = self.post_raw(url=url, data=json.dumps(data),headers=headers)
     return ReturnValue(rawResponse=r)
 
 def add_member_into_chatroom(self, chatroomUserName, memberList,
@@ -486,7 +472,6 @@ def add_member_into_chatroom(self, chatroomUserName, memberList,
         'ChatRoomName' : chatroomUserName,
         memberKeyName  : ','.join([member['UserName'] for member in memberList]), }
     headers = {
-        'content-type': 'application/json; charset=UTF-8',
-        'User-Agent' : config.USER_AGENT}
-    r = self.s.post(url, data=json.dumps(params),headers=headers)
+        'content-type': 'application/json; charset=UTF-8', }
+    r = self.post_raw(url=url, data=json.dumps(params),headers=headers)
     return ReturnValue(rawResponse=r)
diff --git a/itchat/components/login.py b/itchat/components/login.py
index c1fb0391..792cb678 100644
--- a/itchat/components/login.py
+++ b/itchat/components/login.py
@@ -98,8 +98,7 @@ def get_QRuuid(self):
     params = {
         'appid' : 'wx782c26e4c19acffb',
         'fun'   : 'new', }
-    headers = { 'User-Agent' : config.USER_AGENT }
-    r = self.s.get(url, params=params, headers=headers)
+    r = self.get_raw(url=url, params=params)
     regx = r'window.QRLogin.code = (\d+); window.QRLogin.uuid = "(\S+?)";'
     data = re.search(regx, r.text)
     if data and data.group(1) == '200':
@@ -129,8 +128,7 @@ def check_login(self, uuid=None):
     localTime = int(time.time())
     params = 'loginicon=true&uuid=%s&tip=1&r=%s&_=%s' % (
         uuid, int(-localTime / 1579), localTime)
-    headers = { 'User-Agent' : config.USER_AGENT }
-    r = self.s.get(url, params=params, headers=headers)
+    r = self.get_raw(url=url, params=params)
     regx = r'window.code=(\d+)'
     data = re.search(regx, r.text)
     if data and data.group(1) == '200':
@@ -192,9 +190,8 @@ def web_init(self):
         'pass_ticket': self.loginInfo['pass_ticket'], }
     data = { 'BaseRequest': self.loginInfo['BaseRequest'], }
     headers = {
-        'ContentType': 'application/json; charset=UTF-8',
-        'User-Agent' : config.USER_AGENT, }
-    r = self.s.post(url, params=params, data=json.dumps(data), headers=headers)
+        'ContentType': 'application/json; charset=UTF-8', }
+    r = self.post_raw(url=url, params=params, data=json.dumps(data), headers=headers)
     dic = json.loads(r.content.decode('utf-8', 'replace'))
     # deal with login info
     utils.emoji_formatter(dic['User'], 'NickName')
@@ -234,9 +231,8 @@ def show_mobile_login(self):
         'ToUserName'   : self.storageClass.userName,
         'ClientMsgId'  : int(time.time()), }
     headers = {
-        'ContentType': 'application/json; charset=UTF-8',
-        'User-Agent' : config.USER_AGENT, }
-    r = self.s.post(url, data=json.dumps(data), headers=headers)
+        'ContentType': 'application/json; charset=UTF-8', }
+    r = self.post_raw(url=url, data=json.dumps(data), headers=headers)
     return ReturnValue(rawResponse=r)
 
 def start_receiving(self, exitCallback=None, getReceivingFnOnly=False):
@@ -299,10 +295,9 @@ def sync_check(self):
         'deviceid' : self.loginInfo['deviceid'],
         'synckey'  : self.loginInfo['synckey'],
         '_'        : self.loginInfo['logintime'], }
-    headers = { 'User-Agent' : config.USER_AGENT }
     self.loginInfo['logintime'] += 1
     try:
-        r = self.s.get(url, params=params, headers=headers, timeout=config.TIMEOUT)
+        r = self.get_raw(url=url, params=params, timeout=config.TIMEOUT)
     except requests.exceptions.ConnectionError as e:
         try:
             if not isinstance(e.args[0].args[1], BadStatusLine):
@@ -331,9 +326,8 @@ def get_msg(self):
         'SyncKey'     : self.loginInfo['SyncKey'],
         'rr'          : ~int(time.time()), }
     headers = {
-        'ContentType': 'application/json; charset=UTF-8',
-        'User-Agent' : config.USER_AGENT }
-    r = self.s.post(url, data=json.dumps(data), headers=headers, timeout=config.TIMEOUT)
+        'ContentType': 'application/json; charset=UTF-8', }
+    r = self.post_raw(url=url, data=json.dumps(data), headers=headers, timeout=config.TIMEOUT)
     dic = json.loads(r.content.decode('utf-8', 'replace'))
     if dic['BaseResponse']['Ret'] != 0: return None, None
     self.loginInfo['SyncKey'] = dic['SyncKey']
@@ -348,8 +342,7 @@ def logout(self):
             'redirect' : 1,
             'type'     : 1,
             'skey'     : self.loginInfo['skey'], }
-        headers = { 'User-Agent' : config.USER_AGENT }
-        self.s.get(url, params=params, headers=headers)
+        self.get_raw(url=url, params=params)
         self.alive = False
     self.isLogging = False
     self.s.cookies.clear()
diff --git a/itchat/components/messages.py b/itchat/components/messages.py
index 85c0ca2e..7d0b8328 100644
--- a/itchat/components/messages.py
+++ b/itchat/components/messages.py
@@ -273,8 +273,8 @@ def send_raw_msg(self, msgType, content, toUserName):
             'ClientMsgId': int(time.time() * 1e4),
             },
         'Scene': 0, }
-    headers = { 'ContentType': 'application/json; charset=UTF-8', 'User-Agent' : config.USER_AGENT }
-    r = self.s.post(url, headers=headers,
+    headers = { 'ContentType': 'application/json; charset=UTF-8' }
+    r = self.post_raw(url=url, headers=headers,
         data=json.dumps(data, ensure_ascii=False).encode('utf8'))
     return ReturnValue(rawResponse=r)
 
@@ -400,9 +400,8 @@ def send_file(self, fileDir, toUserName=None, mediaId=None, file_=None):
             'ClientMsgId': int(time.time() * 1e4), },
         'Scene': 0, }
     headers = {
-        'User-Agent': config.USER_AGENT,
         'Content-Type': 'application/json;charset=UTF-8', }
-    r = self.s.post(url, headers=headers,
+    r = self.post_raw(url=url, headers=headers,
         data=json.dumps(data, ensure_ascii=False).encode('utf8'))
     return ReturnValue(rawResponse=r)
 
@@ -442,9 +441,8 @@ def send_image(self, fileDir=None, toUserName=None, mediaId=None, file_=None):
         data['Msg']['Type'] = 47
         data['Msg']['EmojiFlag'] = 2
     headers = {
-        'User-Agent': config.USER_AGENT,
         'Content-Type': 'application/json;charset=UTF-8', }
-    r = self.s.post(url, headers=headers,
+    r = self.post_raw(url=url, headers=headers,
         data=json.dumps(data, ensure_ascii=False).encode('utf8'))
     return ReturnValue(rawResponse=r)
 
@@ -481,9 +479,8 @@ def send_video(self, fileDir=None, toUserName=None, mediaId=None, file_=None):
             'ClientMsgId'  : int(time.time() * 1e4), },
         'Scene': 0, }
     headers = {
-        'User-Agent' : config.USER_AGENT,
         'Content-Type': 'application/json;charset=UTF-8', }
-    r = self.s.post(url, headers=headers,
+    r = self.post_raw(url=url, headers=headers,
         data=json.dumps(data, ensure_ascii=False).encode('utf8'))
     return ReturnValue(rawResponse=r)
 
@@ -521,8 +518,7 @@ def revoke(self, msgId, toUserName, localId=None):
         "SvrMsgId": msgId,
         "ToUserName": toUserName}
     headers = {
-        'ContentType': 'application/json; charset=UTF-8',
-        'User-Agent' : config.USER_AGENT }
-    r = self.s.post(url, headers=headers,
+        'ContentType': 'application/json; charset=UTF-8', }
+    r = self.post_raw(url=url, headers=headers,
         data=json.dumps(data, ensure_ascii=False).encode('utf8'))
     return ReturnValue(rawResponse=r)
diff --git a/itchat/components/request.py b/itchat/components/request.py
new file mode 100644
index 00000000..e0eec29d
--- /dev/null
+++ b/itchat/components/request.py
@@ -0,0 +1,11 @@
+def load_request(core):
+    core.post_raw = post_raw
+    core.get_raw = get_raw
+
+def post_raw(self, headers={}, **kwargs):
+    headers.setdefault('User-Agent', self.userAgent)
+    return self.s.post(headers=headers, **kwargs)
+
+def get_raw(self, headers={}, **kwargs):
+    headers.setdefault('User-Agent', self.userAgent)
+    return self.s.get(headers=headers, **kwargs)
diff --git a/itchat/core.py b/itchat/core.py
index 52d6ae4f..8402bbc8 100644
--- a/itchat/core.py
+++ b/itchat/core.py
@@ -2,9 +2,10 @@
 
 from . import storage
 from .components import load_components
+from .config import USER_AGENT
 
 class Core(object):
-    def __init__(self):
+    def __init__(self, proxies=None, userAgent=None):
         ''' init is the only method defined in core.py
             alive is value showing whether core is running
                 - you should call logout method to change it
@@ -27,6 +28,10 @@ def __init__(self):
         self.functionDict = {'FriendChat': {}, 'GroupChat': {}, 'MpChat': {}}
         self.useHotReload, self.hotReloadDir = False, 'itchat.pkl'
         self.receivingRetryCount = 5
+        if proxies:
+            self.s.proxies = proxies
+        self.userAgent = userAgent or USER_AGENT
+
     def login(self, enableCmdQR=False, picDir=None, qrCallback=None,
             loginCallback=None, exitCallback=None):
         ''' log in like web wechat does
@@ -367,6 +372,14 @@ def send(self, msg, toUserName=None, mediaId=None):
             it is defined in components/messages.py
         '''
         raise NotImplementedError()
+    def post_raw(self, url, data=None, json=None, headers={}):
+        '''
+        '''
+        raise NotImplementedError()
+    def get_raw(self, url, params=None, headers={}):
+        '''
+        '''
+        raise NotImplementedError()
     def revoke(self, msgId, toUserName, localId=None):
         ''' revoke message with its and msgId
             for options