diff --git a/client.go b/client.go
index 8b2214c8..d1959868 100644
--- a/client.go
+++ b/client.go
@@ -40,6 +40,9 @@ type Client interface {
 	// WriteCharacteristic writes a characteristic value to a server. [Vol 3, Part G, 4.9.3]
 	WriteCharacteristic(c *Characteristic, value []byte, noRsp bool) error
 
+	// WriteLongCharacteristic writes a characteristic value that is longer than the MTU to a server. [Vol 3, Part F, 3.4.6]
+	WriteLongCharacteristic(c *Characteristic, value []byte) error
+
 	// ReadDescriptor reads a characteristic descriptor from a server. [Vol 3, Part G, 4.12.1]
 	ReadDescriptor(d *Descriptor) ([]byte, error)
 
diff --git a/darwin/client.go b/darwin/client.go
index ef2f979b..591f5463 100644
--- a/darwin/client.go
+++ b/darwin/client.go
@@ -256,6 +256,11 @@ func (cln *Client) WriteCharacteristic(c *ble.Characteristic, b []byte, noRsp bo
 	return nil
 }
 
+// WriteLongCharacteristic writes a characteristic value that is longer than the MTU to a server. [Vol 3, Part F, 3.4.6]
+func (cln *Client) WriteLongCharacteristic(c *ble.Characteristic, b []byte) error {
+	panic("not implemented")
+}
+
 // ReadDescriptor reads a characteristic descriptor from a server. [Vol 3, Part G, 4.12.1]
 func (cln *Client) ReadDescriptor(d *ble.Descriptor) ([]byte, error) {
 	cbdsc, err := cln.pc.findCbDsc(d)
diff --git a/linux/att/client.go b/linux/att/client.go
index ad624020..01c50c58 100644
--- a/linux/att/client.go
+++ b/linux/att/client.go
@@ -422,6 +422,7 @@ func (c *Client) PrepareWrite(handle uint16, offset uint16, value []byte) (uint1
 	req.SetAttributeOpcode()
 	req.SetAttributeHandle(handle)
 	req.SetValueOffset(offset)
+	req.SetPartAttributeValue(value)
 
 	b, err := c.sendReq(req)
 	if err != nil {
@@ -452,7 +453,7 @@ func (c *Client) ExecuteWrite(flags uint8) error {
 	txBuf := <-c.chTxBuf
 	defer func() { c.chTxBuf <- txBuf }()
 
-	req := ExecuteWriteRequest(txBuf[:1])
+	req := ExecuteWriteRequest(txBuf[:2])
 	req.SetAttributeOpcode()
 	req.SetFlags(flags)
 
diff --git a/linux/gatt/client.go b/linux/gatt/client.go
index ef29ff56..7382cda7 100644
--- a/linux/gatt/client.go
+++ b/linux/gatt/client.go
@@ -252,6 +252,26 @@ func (p *Client) WriteCharacteristic(c *ble.Characteristic, v []byte, noRsp bool
 	return p.ac.Write(c.ValueHandle, v)
 }
 
+// WriteLongCharacteristic writes a characteristic value that is longer than the MTU to a server. [Vol 3, Part F, 3.4.6]
+func (p *Client) WriteLongCharacteristic(c *ble.Characteristic, v []byte) error {
+	p.Lock()
+	defer p.Unlock()
+
+	offset := 0
+	prepareWriteLength := 0
+
+	for offset < len(v) {
+		prepareWriteLength = MinInt( len(v) - offset, p.conn.TxMTU()-5 )
+		value := v[offset:offset+prepareWriteLength]
+		if _, _, _, err := p.ac.PrepareWrite(c.ValueHandle, uint16(offset), value ); err != nil {
+			return err
+		}
+		offset += prepareWriteLength
+	}
+
+	return p.ac.ExecuteWrite(0x01) // flags: 0x00=cancel all, 0x01=write all
+}
+
 // ReadDescriptor reads a characteristic descriptor from a server. [Vol 3, Part G, 4.12.1]
 func (p *Client) ReadDescriptor(d *ble.Descriptor) ([]byte, error) {
 	p.Lock()
@@ -401,3 +421,10 @@ type sub struct {
 	nHandler ble.NotificationHandler
 	iHandler ble.NotificationHandler
 }
+
+func MinInt( a int, b int) int {
+	if a < b {
+		return a
+	}
+	return b
+}
\ No newline at end of file