Bike Chain Holder Bicycle Chain Stabilizer MT Bike Roadbike Clean Keeper Tool

Features:
No bearing design, no worry of rusting.
Small size for easy to carry, compatible with 12mm barrel shaft frame.
H shape chain groove with crawler to avoid chain-jumping, more stable.
Sliding shaft with smooth surface for low resistance, easy to slide, simple to clean died corner residue.
Magnet design for easy to fasten spare quick release buttons(not include) or small screws.