A torx head on a screw consists of a star-shaped hole with six vertices into which the torx key fits. Torx screws and wrenches come in various sizes. This 9-piece set of extra long torx keys includes sizes T10, T15, T20, T25, T27, T30, T40, T45 and T50.
The short side has the traditional star shape, while the black ends on the long side fit specifically into the torx head with a point in the middle: Tamper Resistant torx (abbreviated to Torx TR). These cannot be unscrewed with a standard torx wrench, but that is no concern of the owner of this set.
The set of nine extra long wrenches opens a lot of ... screws. Apart from the very smallest sizes (T1 to T9), you will find all average sizes in this handy holder. Including the often-used T27.
Please note: there is no such thing as 'approximately' the right size for torx keys.
