This is a high-quality Archer replacement spur sprocket. This is a 7-tooth .325 pitch sprocket and it comes with a needle bearing. The sprocket fits the following chainsaw models: Husqvarna 40,45, 49 Jonsered 410, 420, 425, 435, 2041, 2045, 2050 

Replaces OEM number 503159802 and Oregon number 10658X and Rotary 36-1604