The Hope RX4+ mineral oil type caliper builds on 25 years of experience designing and manufacturing hydraulic disc brakes, and transfers that knowledge into the world of road and cyclocross drop bar brakes. A precision CNC machined monobloc design results in a stiffer caliper to give unrivaled feel and modulation. Monobloc design creates a stiffer caliper reducing the fuzzy lever feel and brake pad rub Slimline 4 piston lightweight design provides reliable and powerful braking CNC machined from high quality 2014-T6 aluminum offers high strength with the benefit of weight savings Fully servicable design for an extended life Top entry pad fitting make removal or installation simple and fast Versatile design fits 140, 160 & 180mm rotors Mineral Oil Caliper will have Bore Caps with an "M"