The shackle is locked by a double ball bearing mechanism. Unlocking with 90° key rotation. Available with high (protected) or low upper body. Black electrophoretic finish. Retained shackle. Body: Case Hardened Steel. Shackle: Hardened Boron Alloy Steel. Rotating disk or anti-drilling pins in the cylinder provide drilling resistance. Protective shutter prevents dust contamination. Drainage holes prevent freezing. Mul-T-Lock unique high precision 10 telescopic pin tumbler system. Pick and drill resistant for high security needs. Reversible Nickel Silver key with plastic key head and coloured insert for identification. Cen Grade 4Quantity Discount: 10% off 10 or more