This is the Aluminum Stopper Set w/Spring from OFNA Racing. The stoppers along with the spring are used with the throttle/brake return linkage. FEATURES: Aluminum Construction INCLUDES: Six Aluminum Stoppers One Return Spring Six 3x3mm Set Screws REQUIRES: 1.5mm Hex Tool (allen wrench) for assembly SPECS: Spring length: 19mm (0.75") Stopper length: 6.35mm (.025") Stopper outside diameter: 6mm (.235") Stopper inside diameter: 2mm (.078") COMMENTS: Works with most 1/8th scale OFNA kits. NNA 2/17/03 ir/jxs