These shocks feature CNC machined aluminum shock caps, collars, bodies, bottom caps, and hard chrome coated steel shock shafts, all made to exacting tolerances. X-Ring seals are used as the main shaft seal for smooth, low friction action and to prevent leaks. Just like Pro-Line's other Pro-Spec Shocks, the Scalers are meant to stand out from the crowd with bright chrome and blue anodizing. From the top mounting hole to the bottom mounting hole these Pro-Spec Scaler Shocks measure out to be 105mm at full extended length, and collapse down to about 72mm. They include extra 5mm longer shock ends to increase the shock length. These shocks are perfect for super scale rigs! Just like Pro-Line's extremely popular PowerStroke Shocks, the Pro-Spec Scaler Shocks come mostly pre-built (just add oil) and are designed to fit on many popular crawler vehicles. They also include dual rate springs.