Semi-Automatic Drop Down Security Post | CONTROLLER-PLUSSemi Automatic Drop Down Security Post CONTROLLER PLUS Our Semi Automatic Drop Down Security Post from Controller Plus is Ideal for protecting vehicles against theft in private car parks and commercial properties etc. The CONTROLLER PLUS post is very easily operated to lower simply unlock, give a gentle push, and the post reclines. To return to the upright position simply press the pedal located in the base, and it will rise and lock automatically.