T300-PGE-4-HP ductile iron heelproof slotted grates are independently certified to meet Load Class E tested in accordance with EN 1433 134,800 lbs. 600kN. The grate length is 19.69” (.50 m). The grates utilize the patented “Clipfix” grate locking mechanism. The system (channel and grate) provides longitudinal shift protection.