Drive chain tensioner with roller for the Baja Mini Bike MB165 & MB200 (Baja Heat, Mini Baja, Baja Warrior).
The arm on this chain tensioner is 2-5/8 inches long. Older versions were 2-7/8 inches long. The 2-7/8 inch chain tensioner can be found at the link below:
Chain Tensioner with Small Plastic Roller & 2-7/8" Arm for the Baja Mini Bike (Baja Heat, Mini Baja, Baja Warrior)