Professional HEAVY DUTY SOCKETS These bits will allow you to open those Torx/Star male/female fasteners. These are common on most newer domestic and foreign cars. The male sockets have the "hole" that is required for fasteners with impossible "tamper proof" fasteners. (those with a little knob in the center of the star) Features: Professional Tools - Super High Quality Drop Forged Heat Treated Includes those hard to find TAMPER PROOF TORX bits with hole in the center of bit Comes with rails for easy storage in your toolbox. contents: 5 pc 1/4" Drive Female Sockets E4, E5, E6, E7, E8 6 pc 3/8" Drive Female Sockets E10, E12, E14, E16, E18, E20 6 pc 1/4" Drive TAMPER PROOF Male Bits T10, T15, T20, T25, T27, T30 6 pc 3/8" Drive TAMPER PROOF Male Bits T40, T45, T47, T50, T55, T60 1 pc reducer adapter 3/8"Fx1/4"M 3 pc clip-on storage rails