diff --git a/request_test.go b/request_test.go
index 938bc23..d965ab0 100644
--- a/request_test.go
+++ b/request_test.go
@@ -4,7 +4,6 @@ import (
     "midtrans"
     "testing"
     "github.com/cheekybits/is"
-    "midtrans/paytype"
     "encoding/json"
 )
 
@@ -16,11 +15,28 @@ func TestCustomerFieldOmmittable(t *testing.T) {
     }
 
     reqJSON, _ := json.Marshal(req)
-    is.Equal(string(reqJSON), `{"payment_type":"credit_card","transaction_details":{"order_id":"","gross_amount":0},"item_details":null}`)
+    is.Equal(string(reqJSON), `{"payment_type":"credit_card","transaction_details":{"order_id":"","gross_amount":0}}`)
 
     req.CustField1 = "f1"
     req.CustField2 = "f2"
     req.CustField3 = "f3"
     reqJSON, _ = json.Marshal(req)
-    is.Equal(string(reqJSON), `{"payment_type":"credit_card","transaction_details":{"order_id":"","gross_amount":0},"item_details":null,"custom_field1":"f1","custom_field2":"f2","custom_field3":"f3"}`)
+    is.Equal(string(reqJSON), `{"payment_type":"credit_card","transaction_details":{"order_id":"","gross_amount":0},"custom_field1":"f1","custom_field2":"f2","custom_field3":"f3"}`)
+}
+
+func TestBankTransferMandiriBill(t *testing.T) {
+    is := is.New(t)
+
+    req := midtrans.ChargeReq{
+        PaymentType: midtrans.SourceBankTransfer,
+        BankTransfer: &midtrans.BankTransferDetail{
+            MandiriBillBankTransferDetail: &midtrans.MandiriBillBankTransferDetail{
+                BillInfo1: "Silahkan transfer",
+                BillInfo2: "Untuk pembelian pulsa",
+            },
+        },
+    }
+
+    reqJSON, _ := json.Marshal(req)
+    is.Equal(string(reqJSON), `{"payment_type":"bank_transfer","transaction_details":{"order_id":"","gross_amount":0},"bank_transfer":{"bill_info1":"Silahkan transfer","bill_info2":"Untuk pembelian pulsa"}}`)
 }
\ No newline at end of file