The tip with the tri-wing drivers resembles that of some pinwheels and it is made use of to operate on screws which have triangular sockets with 3 wing sizes. For the reason that these screws have these types of different slots, it's difficult to remove them with no tri-wing driver. https://types-of-roof-valley19406.bloggazza.com/28757162/the-fact-about-types-of-screw-heads-pdf-free-download-that-no-one-is-suggesting