This kit includes special high performance components as used on the production 2012-2013 Mustang BOSS 302 and is designed to operate at higher RPMs. This kit fits Mustang 5.0L Coyote engine and features: High-performance BOSS Alternator with 1-way clutch to prevent belt hop-off during upshifts Higher tension belt tensioner Larger pulley to slow the armature speed, reduce drag and reduce parasitic hp loss Also fits M-6007-M50, M-6007-A50NA, M-6007-A50XS and M-6007-A50SC Ford Racing crate engines Kit includes OEM Mustang BOSS 302 alternator, tensioner, idler pulley, belt and mounting hardware