The Master Lock No. 1479TAT features two 5/8in (16mm) Class III/IV Barbell™ receiver locks, keyed alike. The receiver lock includes the Push to Lock™ locking mechanism, easily used by pushing the lock body firmly onto the pin and removing the key. The Weather Tough® seal and water tight cap provides additional protection from moisture and dirt. The Limited Lifetime Warranty provides peace of mind from a brand you can trust.