Premium gold series Motocross chain. Lightweight, high-strength chromoly construction for today’s high-powered 4-Strokes. 8,800 lbs. tensile strength for 125 to 530cc applications. The PT520 MX was designed to handle the increasing horsepower demands of today’s 4-Stroke motorcycles; all components of the chain use a ProTaper exclusive heat-treating process to aid in the life of and durability of the chain. Designed for 125cc to 530cc applications. Lightweight, ultra high-strength chromoly construction with 8,000 lbs. of tensile strength.