Chemical Cart, has two open shelves with rigid PVC extrusions on two sides to prevent containers from sliding off.The lower shelf also has rigid plastic guard rails on both ends.Additional features: 4" diameter casters, two with toe locks!ready-to-roll, full factory assembly!ergonomic, extruded rubber handle grips!durable glacier white, epoxy-coated 18 gauge welded tubular steel frame!ID tag!supports loads up to 400 lbs.!lifetime guarantee.