Replacing your coilover’s shock absorbers is key to a smoother, safer ride. Struts are wear-and-tear items that absorb countless bumps and should be inspected every 12,000 miles. It’s always recommended to replace shocks in pairs. All F2 coilover kits are labeled with a unique identifier or serial number. Serial numbers are located on the gold shock body. To ensure fitment, please provide the serial number at the time order is placed.