This Thule style D arm locking system has a unique 2 locks. One lock at the top of the D arm and one at the lowest part of the D arm.
Designed for extra security and safety when in one of its locked positions
Designed to lock in 3 positions:
A. Giving added visible security by locking across the door of the caravan or motorhome.
B. Can be locked in an outward facing position can be used to assist when entering the caravan or motorhome.
C. Can also be locked in a third position away from the door when neither of the first 2 positions are required.