The EradiSpeed+ is a direct replacement 2pc rotor for the 1992-2002 Dodge Viper. This is designed to work with the stock 4 piston brake system. These 13 inch rotors feature directional vanes, which advances cooling efforts, and are a 2pc design with an anodized black 6061-T6 aluminum center hat bolted to the rotor ring, greatly reducing weight.Rotor Diameter:13 inch 2-piecePiston Count:Uses your existing stock calipers.Pad Type:Uses stock pads.Includes:13 inch 2-piece rotor assemblies for front rotors upgradeNotes:Designed to be used with the Stock Viper 4 piston calipers.