Trapezoidal timing belts and pulleys maintain consistent synchronous drive rotation in most common industrial conveying, light manufacturing, and agricultural environments. MXL series timing belt pulleys have a very small 0.080 inch pitch. XL series timing belt pulleys have a small 0.20 inch pitch. L series timing belt pulleys have a medium 0.375 inch pitch. H series timing belt pulleys have a medium-large 0.5 inch pitch.