1999 Silverado FOB set up

I have tried all of the tips on setting my remote with no success. I purhased this transmitter on EBay. There is a code on the back of the transmitter but how do I found out if its the one for my 1999 Silverado SWB?

Thanks

take your vin number to the dealers parts department. They can look up the fob and it should give them the number on the back.

Thank you. Dealer gave me a different number and as I thought, I was ripped off by the Ebay seller. The Dealer gave me the correct # to look for.

Thanks for you help!