2-Pack NAPA Gates 25 9590 XL Cogged Replacement V-Belt 31/64" x 59 3/8" Brand New High Capacity V-Belt (Standard) 31/64" x 59 3/8" Automotive XL V-Belt is a durable, long-lasting replacement V-belt designed for the most demanding engine drives. Due to thermal forces in the vehicle engine, this variable notched belt tightens on the drive as it heats up to prevent slippage, improve belt performance and reduce noise. Fiber-loaded rubber stock adds flexibility along the length of the belt and provides greater lateral stability in the pulley Form-ground to ensure precise top width and sidewall dimensional control for proper fit to the pulley Thermally-active tensile cords for maintenance-free performance when properly installed and tensioned Resists oil, heat, ozone, weather and aging for improved belt life Meets or exceeds SAE J636C specifications