This screw has become a widely used fastener in model building. It really does have a million uses!  You can mount your servos, but also great for canopies, cowls, hatches, landing gear straps and much  more. It has a self-contained washer that completely covers the servo grommets and acts as a normal  washer on other applications. It has a deep non-slip socket head that takes a 5/64 hex (Allen wrench) or Ball Driver.