. Aftermarket Carburetor 
Fits 
MTD Troy-Bilt 120R 121R 320BVR 410 600R 705R 725R 
Replace part numbers: 
ECHO 000721 / 13001013410 
ECHO A021000380/ A021000381/ A021000382/ A021000720/ A021000721/ A021000722 
OREGON 50-621 
ZAMA RB-K66A / RB-K70A / RBK66B 
Fitment: 
Echo models GT200, GT201, SRM200, SRM201, SRM130, SRM231, SRM230 HC160 HC180, & HC200