Promax C-1 Chain Tensioner - 2-Hole Fits 3/8"/10mm Axles Gold. Promax C-1 chain tensioners are extruded then CNC-machined from 6061-T6 aluminum for optimal strength and low weight. Two mounting holes ensure adjustability on most frames. When used properly they will protect your frame dropouts and help hold your rear wheel in place.

CNC-machined 6061-T6 aluminum

For use with 3/8" and 10mm axles

Two axle hole design