Our 2007-2018 Jeep Wrangler JK rear long arm brackets are designed to be100% bolt on. We spent countless hours designing these1/4 inch bracketsin 3D Solidworks providing you asuperior fit.These brackets bolt on using eight 1/2 bolts to interior brackets. The interior brackets have preinstalled pem fasteners to easily and securely hold all your bolts in place. This provides asuperior clamping forcethen trying to clamp the entire frame. These brackets incorporate both upper and lower long arm mounts providing you the ability to run4 true long armsin the rear of your JK. Both upper and lower mounting locations use a9/16 bolt, and have a 2 5/8sinside diameter. CNC Laser Cut & Bent 1/4″ Steel Bolt On Design Pem Fasteners For Easier Installation Clamps To Frame With 8 Bolts Per Side MADE IN THE USA! Fits:Jeep Wrangler JK 2 Door (2007-2018)Jeep Wrangler JK 4 Door Unlimited (2007-2018)