The E series HD dual lock pack is a faster, easier, and better way to securely lock both the ball holder to the drop bar and the drop bar in the receiver. Securely locks both the ball holder to the drop bar and the drop bar in the receiverHigh strength ball interlock for simple, smooth and secure lockingDrill resistant barrel lock is an extra level of protectionCannot be false locked1/4 Turn lock and unlock is fast and easyWater tight dust cap and o-ring extend lock life by protecting it from dirt and water