Master Lock bent pin receiver lock features a Swivel Head™ design for easy access when locking and unlocking Stainless steel locking head with a covered key way offers ultimate corrosion resistance and protection from moisture, dirt, and grime Swivel Head™ design also has hardened receiver pins for increased sheer strength and a precision 4-pin tumbler locking mechanism resists picking Fits 1/2 and 5/8 receiver holes.