The Dirt Logic 4.0 provides the ultimate in hardcore offroad dampening capacity with superior highway comfort in a big package. This massive high end shock is designed for full size vehicles that required the biggest and best Coilover shock in a bolt on configuration. Nothing else comes close. Features - 4.0" OD Stainless Steel Body. - 3 5/8" OD Billet Aluminum Piston. - 1.25" NitroSteel? Black Piston Rod. - Adjustable Coilover Construction. - 3/4" Spherical Ball Mounting Ends. - 4.0" OD Piggyback, Remote Resi or Non Resi.