Topeak Super Chain Tool SOFTGOODS SHIMANO's SM-JC41 Junction B is

SHIMANO's SM-JC41 Junction B is the central connector for DI2 systems

4 crank arm lengths – 165

this is an exciting challenge

aero extensions

the expected sealant lifespan is:

Topeak Super Chain Tool SOFTGOODS SHIMANO's SM-JC41 Junction B isHigh quality chain tool for single and multi speed chains up to 12 speed, NOT including Campagnolo 11 speed hollow pin chains. Contains 5 and 6 mm Allen wrenches, and chain hook. Specifications FUNCTIONS 7 ALLEN WRENCHES 5 6 mm CHAIN TOOL CrMo steel CHAIN HOOK Steel wire TOOL MATERIAL Hardened steel BODY Hardened steel SIZE 7. 6 x 4 x 1. 9 cm 3. 0 x 1. 6 x 0. 7 ADDED FEATURES Secondary chain link fence Chain pin breaker, Chain pin holder Mfr Claimed