ReadyLIFT OEM-style rear block kits are available for 2011-2016 Ford Super Duty model specific applications. These 4.0" Rear Block Kits include two (2) Rear Blocks four (4) 15.5" Long E-Coated U-Bolts eight (8) Nuts and Washers and one (1) Carrier Bearing Spacer. Based on OEM designs and never made out of light weight extrusions our 4" 2011-2016 Ford Super Duty Blocks have Integrated OEM-Style Bump Stops. ReadyLIFT Block Kits will put a slight rake back in your truck for hauling or towing and are designed to work with your ReadyLIFT Suspension Leveling Kit. In fact these blocks are the ideal Tow Package upgrade for not only for stock height vehicles but lifted or leveled trucks too! Like all ReadyLIFT products these block kits come with our Limited Lifetime Warranty. Note: 66-2014 4" block is for use on 2011-2016 Ford F250 or F350 Super Duty 2WD/4WD trucks with a 2-piece drive shaft. Lift height will vary depending on what factory block your truck has. NOTE: The lift blocks in this kit are not designed to work with aftermarket or factory add-on air spring/load leveling kits that attach to the bump stop tangs. Use of this type of air bag system will void all block warranties and can cause failure of the block bump stop tang.