A crucial part of the spiderlight holster system the pin attaches to the plate and the plate attaches to your cameras tripod socket the entire rig slides and locks into the holster where the 2 position locking system secures your camera in the lower position your equipment is locked and fully secure you still have camera security while in the upper position but its now ready to be drawn and take your shot with an anti twist design the plate wont interfere with battery compartment acce