diff --git a/src/Redsys/Tpv/Tpv.php b/src/Redsys/Tpv/Tpv.php
index ce87fca..08454c5 100644
--- a/src/Redsys/Tpv/Tpv.php
+++ b/src/Redsys/Tpv/Tpv.php
@@ -133,14 +133,27 @@ public function setFormHiddens(array $options)
     }
 
     public function getFormHiddens()
+    {
+        $hiddens = '';
+
+        foreach ($this->getFormValues() as $key => $value) {
+            $hiddens .= $this->getInputHidden($key, $value);
+        }
+
+        return $hiddens;
+    }
+
+    public function getFormValues()
     {
         if (empty($this->values)) {
             throw new Exception('Form fields must be initialized previously');
         }
 
-        return $this->getInputHidden('SignatureVersion', $this->options['SignatureVersion'])
-            .$this->getInputHidden('MerchantParameters', $this->getMerchantParametersEncoded())
-            .$this->getInputHidden('Signature', $this->getValuesSignature());
+        return array(
+            'SignatureVersion' => $this->options['SignatureVersion'],
+            'MerchantParameters' => $this->getMerchantParametersEncoded(),
+            'Signature' => $this->getValuesSignature()
+        );
     }
 
     public function getInputHidden($name, $value)
diff --git a/tests/Redsys/Tpv/TpvTest.php b/tests/Redsys/Tpv/TpvTest.php
index 5353230..7cbe8f3 100644
--- a/tests/Redsys/Tpv/TpvTest.php
+++ b/tests/Redsys/Tpv/TpvTest.php
@@ -100,6 +100,10 @@ public function testFormFields($tpv)
             'MerchantURL' => 'http://example.com',
         ]);
 
+        $values = $tpv->getFormValues();
+
+        $this->assertTrue(count($values) === count(array_filter($values)));
+
         $fields = $tpv->getFormHiddens();
 
         $this->assertContains('<input', $fields);