diff --git a/README.markdown b/README.markdown
index 65d5086..9a9d9dc 100644
--- a/README.markdown
+++ b/README.markdown
@@ -16,6 +16,7 @@ Para todas as validações é retornado um boolean se a condição é valida ou
 ### Validando apenas o número de cartão
 ``` javascript
 moip.creditCard.isValid("4111111111111111");    //return true
+moip.creditCard.isValid("4111111111111111", ["MASTERCARD", "AMEX"]);    //return false
 moip.creditCard.isValid("4111 1111-1111.1111"); //return true
 moip.creditCard.isValid("1919191919191919");    //return false
 moip.creditCard.isValid("41111");               //return false
@@ -33,16 +34,16 @@ Possíveis retornos:
 
 ### Identificando a bandeira de um cartão
 ``` javascript 
-moip.creditCard.cardType("5105105105105100");    //return [Object]MASTERCARD
+moip.creditCard.cardType("5105105105105100", ["ELO", "VISA", "MASTERCARD", "AMEX", "HIPERCARD", "DINERS"]);    //return [Object]MASTERCARD
 moip.creditCard.cardType("4111111111111111");    //return [Object]VISA
-moip.creditCard.cardType("341111111111111");     //return [Object]AMEX
-moip.creditCard.cardType("30569309025904");      //return [Object]DINERS
-moip.creditCard.cardType("3841001111222233334"); //return [Object]HIPERCARD
-moip.creditCard.cardType("4514160123456789");    //return [Object]ELO
-Moip.creditCard.cardType("6370950000000005");    //return [Object]HIPER
-moip.creditCard.cardType("9191919191919191");    //return [Object]null
+moip.creditCard.cardType("341111111111111", ["ELO", "VISA", "MASTERCARD", "AMEX", "HIPERCARD", "DINERS"]);     //return [Object]AMEX
+moip.creditCard.cardType("30569309025904", ["ELO", "VISA", "MASTERCARD", "AMEX", "HIPERCARD", "DINERS"]);      //return [Object]DINERS
+moip.creditCard.cardType("3841001111222233334", ["ELO", "VISA", "MASTERCARD", "AMEX", "HIPERCARD", "DINERS"]); //return [Object]HIPERCARD
+moip.creditCard.cardType("4514160123456789", ["ELO", "VISA", "MASTERCARD", "AMEX", "HIPERCARD", "DINERS"]);    //return [Object]ELO
+Moip.creditCard.cardType("6370950000000005", ["ELO", "VISA", "MASTERCARD", "AMEX", "HIPERCARD", "DINERS"]);    //return [Object]HIPER
+moip.creditCard.cardType("9191919191919191", ["ELO", "VISA", "MASTERCARD", "AMEX", "HIPERCARD", "DINERS"]);    //return [Object]null
 
-card = moip.creditCard.cardType("5105105105105100"); 
+card = moip.creditCard.cardType("5105105105105100", ["ELO", "VISA", "MASTERCARD", "AMEX", "HIPERCARD", "DINERS"]); 
 cardIs = card.brand; // MASTERCARD
 ```
 Possíveis retornos:
diff --git a/build/moip.js b/build/moip.js
index 3325305..ad729d5 100644
--- a/build/moip.js
+++ b/build/moip.js
@@ -45,7 +45,7 @@
             }
         },
 
-        cardType: function(creditCardNumber, loose) {
+        cardType: function(creditCardNumber, bandeiras, loose) {
             var brands = {
                     VISA:       { matches: function(cardNum){ return /^4\d{15}$/.test(cardNum); } },
                     MASTERCARD: { matches: function(cardNum){ return /^5[1-5]\d{14}$/.test(cardNum); } },
@@ -100,12 +100,57 @@
             // order is mandatory:
             // a) VISA is identified by the broad prefix '4', shadowing more specific ELO prefixes
             // b) HIPERCARD has precendence over DINERS for prefix 3841 (loose check)
-            if (brands.ELO.matches(creditCardNumber))          { return {brand:'ELO'}; }
-            if (brands.VISA.matches(creditCardNumber))         { return {brand:'VISA'}; }
-            if (brands.MASTERCARD.matches(creditCardNumber))   { return {brand:'MASTERCARD'}; }
-            if (brands.AMEX.matches(creditCardNumber))         { return {brand:'AMEX'}; }
-            if (brands.HIPERCARD.matches(creditCardNumber))    { return {brand:'HIPERCARD'}; }
-            if (brands.DINERS.matches(creditCardNumber))       { return {brand:'DINERS'}; }
+            if( bandeiras ){
+                if (brands.ELO.matches(creditCardNumber)){ 
+                    var index = bandeiras.indexOf("ELO");
+                    if( index != -1 ){
+                        return { brand:'ELO' };
+                    }
+                    return null;
+                }
+                if (brands.VISA.matches(creditCardNumber)){ 
+                    var index = bandeiras.indexOf("VISA");
+                    if( index != -1 ){
+                        return { brand:'VISA' };
+                    }
+                    return null;
+                }
+                if (brands.MASTERCARD.matches(creditCardNumber)){ 
+                    var index = bandeiras.indexOf("MASTERCARD");
+                    if( index != -1 ){
+                        return { brand:'MASTERCARD' };
+                    }
+                    return null;
+                }
+                if (brands.AMEX.matches(creditCardNumber)){ 
+                    var index = bandeiras.indexOf("AMEX");
+                    if( index != -1 ){
+                        return { brand:'AMEX' };
+                    }
+                    return null;
+                }
+                if (brands.HIPERCARD.matches(creditCardNumber)){ 
+                    var index = bandeiras.indexOf("HIPERCARD");
+                    if( index != -1 ){
+                        return { brand:'HIPERCARD' };
+                    }
+                    return null;
+                }
+                if (brands.DINERS.matches(creditCardNumber)){ 
+                    var index = bandeiras.indexOf("DINERS");
+                    if( index != -1 ){
+                        return { brand:'DINERS' };
+                    }
+                    return null;
+                }
+            }else{
+                if (brands.ELO.matches(creditCardNumber))          { return {brand:'ELO'}; }
+                if (brands.VISA.matches(creditCardNumber))         { return {brand:'VISA'}; }
+                if (brands.MASTERCARD.matches(creditCardNumber))   { return {brand:'MASTERCARD'}; }
+                if (brands.AMEX.matches(creditCardNumber))         { return {brand:'AMEX'}; }
+                if (brands.HIPERCARD.matches(creditCardNumber))    { return {brand:'HIPERCARD'}; }
+                if (brands.DINERS.matches(creditCardNumber))       { return {brand:'DINERS'}; }
+            }
             
             return null;
         },
diff --git a/src/creditCard.js b/src/creditCard.js
index 72ae019..aa5b6b0 100644
--- a/src/creditCard.js
+++ b/src/creditCard.js
@@ -45,7 +45,7 @@
             }
         },
 
-        cardType: function(creditCardNumber, loose) {
+        cardType: function(creditCardNumber, bandeiras, loose) {
             var brands = {
                     VISA:       { matches: function(cardNum){ return /^4\d{15}$/.test(cardNum); } },
                     MASTERCARD: { matches: function(cardNum){ return /^5[1-5]\d{14}$/.test(cardNum); } },
@@ -100,12 +100,57 @@
             // order is mandatory:
             // a) VISA is identified by the broad prefix '4', shadowing more specific ELO prefixes
             // b) HIPERCARD has precendence over DINERS for prefix 3841 (loose check)
-            if (brands.ELO.matches(creditCardNumber))          { return {brand:'ELO'}; }
-            if (brands.VISA.matches(creditCardNumber))         { return {brand:'VISA'}; }
-            if (brands.MASTERCARD.matches(creditCardNumber))   { return {brand:'MASTERCARD'}; }
-            if (brands.AMEX.matches(creditCardNumber))         { return {brand:'AMEX'}; }
-            if (brands.HIPERCARD.matches(creditCardNumber))    { return {brand:'HIPERCARD'}; }
-            if (brands.DINERS.matches(creditCardNumber))       { return {brand:'DINERS'}; }
+            if( bandeiras ){
+                if (brands.ELO.matches(creditCardNumber)){ 
+                    var index = bandeiras.indexOf("ELO");
+                    if( index != -1 ){
+                        return { brand:'ELO' };
+                    }
+                    return null;
+                }
+                if (brands.VISA.matches(creditCardNumber)){ 
+                    var index = bandeiras.indexOf("VISA");
+                    if( index != -1 ){
+                        return { brand:'VISA' };
+                    }
+                    return null;
+                }
+                if (brands.MASTERCARD.matches(creditCardNumber)){ 
+                    var index = bandeiras.indexOf("MASTERCARD");
+                    if( index != -1 ){
+                        return { brand:'MASTERCARD' };
+                    }
+                    return null;
+                }
+                if (brands.AMEX.matches(creditCardNumber)){ 
+                    var index = bandeiras.indexOf("AMEX");
+                    if( index != -1 ){
+                        return { brand:'AMEX' };
+                    }
+                    return null;
+                }
+                if (brands.HIPERCARD.matches(creditCardNumber)){ 
+                    var index = bandeiras.indexOf("HIPERCARD");
+                    if( index != -1 ){
+                        return { brand:'HIPERCARD' };
+                    }
+                    return null;
+                }
+                if (brands.DINERS.matches(creditCardNumber)){ 
+                    var index = bandeiras.indexOf("DINERS");
+                    if( index != -1 ){
+                        return { brand:'DINERS' };
+                    }
+                    return null;
+                }
+            }else{
+                if (brands.ELO.matches(creditCardNumber))          { return {brand:'ELO'}; }
+                if (brands.VISA.matches(creditCardNumber))         { return {brand:'VISA'}; }
+                if (brands.MASTERCARD.matches(creditCardNumber))   { return {brand:'MASTERCARD'}; }
+                if (brands.AMEX.matches(creditCardNumber))         { return {brand:'AMEX'}; }
+                if (brands.HIPERCARD.matches(creditCardNumber))    { return {brand:'HIPERCARD'}; }
+                if (brands.DINERS.matches(creditCardNumber))       { return {brand:'DINERS'}; }
+            }
             
             return null;
         },