Oregon 21358 RIM SPROCKET KIT C/S 3/8 STD ECHO: 175005-14330 used on Echo CS450, CS451, CS452, CS500 & CS550. 3/8 Std. 

Replaces
ECHO: 175005-14330
Rotary: 14981

Fits Models
ECHO: CS450, CS451, CS452, CS500, CS510EVL, CS550, CS610

SR-5