Check the listing for details. Quadboss QB426 Drive Belt. Condition: New. Listed at 72.60 USD. Drive Belt (QB426) by Quadboss®. TQX: Recommended for engine displacement of 1,000 cc and lower. High-strength, low-stretch aramid cords and specially formulated compression compounds engineered for high-horsepower, large-displacement engines. Delivers the increased strength and durability needed to ensure long-lasting performance for today's extreme machines and the most aggressive riders. PRO: Recommended for engine displacement of 650 cc and lower. Designed to dominate any type of terrain. Constructed of an engineered fiber-loaded neoprene compound with strong p-aramid cord reinforcement. Delivers the muscle and the durability demanded by today's high-performance engines and high-performance enthusiasts. Runs cooler and provides long belt life. SEL: Recommended for engine displacement of 500 cc and lower.