These standard drain covers are built in three different thicknesses for varying applications. The 3/16 inch thick covers are recommended for foot traffic and light automotive traffic depending on the width, the 3/8 are for automotive traffic and light industrial/Ag traffic, and the 1/2 inch drains are built for heavier industrial/Ag (tractors, semi trucks, and forklifts). Our drain covers are built for almost any environment (warehouses, residential and commercial shops, outdoor applications and more). If you are having a hard time deciding on which thickness best suits your needs contact us using the info below and we can help.