Genuine GT-LOCK^TM Roller Door Lock - Model: GT-LOCK-INT is an internal high Security lock  which allows you to secure the door to the ground internally. Designed to suit most garage doors including panel, tilta, roller, barn. Condition is Brand New. Anchor to floor. This model offers the high security FastDrive Concrete Anchor pins. These offer a massive 14.9kN shear strength when installed into 32MPa slab (When installed as per manufacturers installation method)