Apex Tri-Wing ® bits. The Tri-Wing bit, also known as triangular slotted, screw drive has three radial slots. Tri-Wing, as the name suggests, is a screw with three ”wings” and a small triangular hole in the center. Quality design and construction give Apex Tri-Wing bits a long service life and durability. With Apex Tri-Wing bits you are assured of high quality and industrial strength.