The New Shape of Strength Prest Lock 2 New Design is Fast to Install and 20% Stronger. Talk about extra-strength! Now you can have a teardrop locking system that's not only quick and easy to install but far stronger, too. New Prest Lock 2 is a totally enclosed tube upright that is 20% stronger than traditional open back uprights. Prest Lock 2 teardrop locks make it easy to change/adjust rack ...