Feature: Effectively prevent chain drop and chain jump For single-piece sprocket; the middle shaft and crank need to be removed for installation High-strength aluminum alloy heat treatment processing, CNC turning process lightweight design, fine workmanship Middle shaft chain stabilizer is compatible with 30-40T discs Specification: Product name: BB middle shaft chain stabilizer Material: aluminum alloy+ nylon Color: black, red Specifications: Suitable for threaded BB middle shaft(press-in type is not supported yet) Weight: about 81.3 grams(including packaging) Size: as shown Package Content： Middle shaft chain stabilizer*1 Note: 1. The real color of the item may be slightly different from the pictures shown on website caused by many factors such as brightness of your monitor and light brightness. 2. Please allow slight manual measurement deviation for the data. Features: Black Bike Chain Stabilizer for Effortless and Reliable Chain Management Material: light weight, good strength and well temperature resistance, good impact resistance Appearance and performance: automatic cutting, smooth edge, fit most of the road bicycles, delicate texture. Compatibility: smooth surface and exquisite workmanship, fit most of the bicycles. Easy Installation: Brand new and high quality, easy to install.