I ordered for this product but received something else. Because I had an urgent requirement, I can't replace the product.

Apparently the product I received is working well. I have tested it with ARDUINO UNO and LEONARDO. Use TX, RX, GND pins on board and connect to arduino and start software serial. If you have RS232 to USB converter, you can connect it to your PC as well.

But the seller didnot even bother to inform me that we don't have the specified product, instead he shipped whatever h...

The product advertised is not the same as the product received. I have contacted FlipKart to look into this issue. Hopefully they will revert / sort out this problem. It is strange that such sellers are being allowed on this website.