I AM SELLING A NEW TEAM SPROCKET ARCTIC CAT #351513-006, 21T X 13W X 13 INTERNAL 

The  is a standard top gear used in the chaincase drive system of various pre-1996 Arctic Cat and pre-2003 Polaris, Ski-Doo, and Yamaha snowmobiles. 
Compatible Snowmobiles and Applications 
The sprocket is used in a range of older snowmobile models. According to SpazCycle, specific compatible Arctic Cat models include: 
It is also compatible with many Polaris models from 1993-1995, such as the 440 XCR, Indy RXL, and various Indy XLT versions. 
Product Specifications

Please check with your local dealership to ensure proper fit for your machine.