Full-closing Wilton Brute Force™ extra-heavy-duty C-clamp stands up to the rigorous demands of ship building, bridge building, and other heavy industrial and construction applications. The forged steel square-throat frame and steel spindle feature a black oxide finish for outstanding corrosion resistance. A hot upset square spindle head withstands higher torques.• Throat depth 4-1/4 • Load capacity 40,000 lb. C-Clamp, 12-3/8 , Steel, Extra HD, 40, 000 lb This product contains a chemical that is regulated under California Proposition 65. Warning This product contains a chemical known to the State of California to cause cancer. Warning This product contains a chemical known to the State of California to cause birth defects or other reproductive harm.