UMI Performance Spring Spacer KitUMIs rear spring spacers may be just the ticket to achieve that perfect stance or prevent tire rub. UMIs zinc coated, laser cut mild steel spacers are available in 1 8 and 3 16 thickness and can be safely stacked. They provide an easy way to fine tune the rear ride height of your GM A, G and F Body. No cutting, welding or drilling required. We recommend these for fine tuning only, and maximum adjustment amount is the responsibility of the installer.