Yeah Racing Desert Lizard Piggyback Shocks with Reservoir are an internal spring shock option intended for any crawler application requiring 90, 100mm or 110mm length shocks. Featuring double O-rings and sealed cartridges to prolong the life of the shocks. These piggyback versions allow for a more controlled compression and rebound. Package includes two assembled shocks, two reservoirs, two lengths of tubing with preinstalled connectors and hardware.