Features: * Made for Zenoah 20 to 29cc or equivalent engine. * High gloss polished mirror finish. * M5 machined bolts with lock washers for mounting. * CNC machined exhaust mount and port. * Tunable exhaust port diameter (Exhaust port plate can be applied for increased back pressure). * Unique set screw bolt locking mechanism. Specifications: * Length: 335mm * Diameter: 51mm * Weight: 220g * Exhaust ID: 16mm