Campagnolo 11 Speed Chain Tool
The 5.5mm width of the Campagnolo's 11 speed Ultra Shift chains require you to use only the 11 speed only chain tool to join an 11 speed chain Campagnolo chain. This is different to the 10 speed tool!
Additionally you MUST use the 11 speed Ultra-link to join the chain.
Please see the link below for a how to guide for this procedure if you are at all unsure of the process.
