Zone Offroad strut spacers are manufactured in the US. For the Ford F150 they use an offset design to ensure the coil clears the A-arm at full droop. Hardware is upgraded from factory specs from 10mm 10.9 fasteners to 7/16" grade 8 bolts. Zone strut spacers are made from Polyphthalamide which is a thermoplastic synthetic resin commonly used to replace metals in automotive applications. This material will hold up to anything as well as provide long term corrosion reistance. This lift is engineered to be simple to install not requiring disassembly of the strut and will maintain the factory ride quality.