diff --git a/lib/httpClient.js b/lib/httpClient.js
index e9b0f4e..8170fa4 100644
--- a/lib/httpClient.js
+++ b/lib/httpClient.js
@@ -13,11 +13,12 @@ class HttpClient{
     this.parent = parentObj;
     this.http_client = axios.create();
   }
-  request(httpMethod,serverKey,requestUrl,firstParam={},secondParam={}){
+  request(httpMethod,serverKey,requestUrl,firstParam={},secondParam={},extraHeaders={}){
     let headers = {
       'content-type': 'application/json',
       'accept': 'application/json',
-      'user-agent': 'midtransclient-nodejs/1.4.3'
+      'user-agent': 'midtransclient-nodejs/1.4.3',
+      ...extraHeaders
     };
 
     let reqBodyPayload = {};
diff --git a/lib/snap.js b/lib/snap.js
index 27852c4..80c5a92 100644
--- a/lib/snap.js
+++ b/lib/snap.js
@@ -16,33 +16,38 @@ class Snap{
   /**
    * Do `/transactions` API request to Snap API
    * @param  {Object} parameter - object of Core API JSON body as parameter, will be converted to JSON (more params detail refer to: https://snap-docs.midtrans.com)
+   * @param  {Object} headers - object of http headers to add to request
    * @return {Promise} - Promise contains Object from JSON decoded response
    */
-  createTransaction(parameter={}){
+  createTransaction(parameter={},headers={}){
     let apiUrl = this.apiConfig.getSnapApiBaseUrl()+'/transactions';
     let responsePromise = this.httpClient.request(
       'post',
       this.apiConfig.get().serverKey,
       apiUrl,
-      parameter);
+      parameter,
+      undefined,
+      headers);
     return responsePromise;
   }
   /**
-   * Wrapper function that call `createTransaction` then:
+   * Wrapper function that call `createTransaction` and returns token
+   * @param  {Object} headers - object of http headers to add to request
    * @return {Promise} - Promise of String token
    */
-  createTransactionToken(parameter={}){
-    return this.createTransaction(parameter)
+  createTransactionToken(parameter={},headers={}){
+    return this.createTransaction(parameter, headers)
       .then(function(res){
         return res.token;
       })
   }
   /**
-   * Wrapper function that call `createTransaction` then:
+   * Wrapper function that call `createTransaction` then returns redirect_url
+   * @param  {Object} headers - object of http headers to add to request
    * @return {Promise} - Promise of String redirect_url
    */
-  createTransactionRedirectUrl(parameter={}){
-    return this.createTransaction(parameter)
+  createTransactionRedirectUrl(parameter={},headers={}){
+    return this.createTransaction(parameter, headers)
       .then(function(res){
         return res.redirect_url;
       })