KMC E12 EPT 12 Speed E-Bike Chain, 136 Links, Dark Silver 47364720Specially designed for mid engine driven e bikes such as Bosch, Panasonic and AEG, These chains have higher TORSION resistance to cope with ruthless shifting and hi torque This chain is compatible with 12x Campagnolo, Shimano and Sram MTB. They are not compatible with Sram road groups, this is due to a difference in pin length EcoProTeQ (EPT): Anti Rust technology, Surpasses 650 hours Salt Spray Test Triple X durability, unmatched chain life KMC