Integy four pack of piggy back shocks are purple anodized shock bodies with aluminum construction. Threaded shock bodies Team Integy logo and web address printed on the piggyback (reservoir) The piggyback design is built to reduce air bubbles and provide additional shock oil volume. Comes with two 20lbs rate springs (red) and two 25lbs rate springs (blue) Red anodized inboard shock mounts Assembled with two hole pistons, but the shocks are not filled with oil. INCLUDES: Four assembled shocks (shocks comes without oil) Four, four hole shock pistons (two holes come installed) Four shock bushings Four 3mm X 10mm allen head screws Four 3mm x 15mm countersunk head screws Four 3mm X 3mm set screws Four piggyback (reservoir) foam inserts Four o-rings Four aluminum spacers Two aluminum inboard shock mounts . SPECS: Length: 4-1/8" (105mm) Diameter: 5/8" ( 16mm)