FNSL4R-MC4 Big Brake Rear Axle Kits area novel way add disc brakes with an effective parking brake actuation using the MC4 parking brake assembly as a compliment to front big brake upgrades on late model high performance vehicles. High capacity braking from the FNSL4R calipers, BP-10 compound pads, and oversized 12.88" rotors are matched to the OE master cylinder output, ABS function, and individual vehicle bias requirements. Enhanced brake performance, increased durability, and high-tech style compliment big wheel, tire, and suspension upgrades on customized vehicles and all others with increased brake requirements.