I bought a Casio calculator from WS Retail and got the product with tampered serial number where as per brand there is a serial number which is pasted over the packaging as well as the invoice of the product and is entitled for warranty only if the two captioned conditions are fulfilled, but if there is some sort of tampering involved than it could be a grey market or a fake product.
I would not suggest any one to buy the product from flipkart as they are cheating customers.
Order ID - OD201161204181711200