The cable hook designed to organize cables up to 8 mm in diameter. The hook can be screwed directly onto your IKEA Ivar shelf using a 3.5 x 16 mm wood screw with a countersunk head. There are two versions of the hook: a normal version that requires a screwdriver, and a "lazy" version with a larger hole that allows a standard bit holder to be used for the cordless screwdriver.