1/2" Hexagon Socket (23mm)

It turns up on certain Japanese vehicles, on some agricultural and industrial machinery, on imported plant, and on a scattering of hydraulic and pneumatic fittings. The list is short, which is precisely the problem: no general socket set includes it, so the first 23mm nut anybody meets is a surprise.

What people do instead is worth understanding, because both options are bad. A 22mm will not go on. A 24mm will slip over it and engage only at the extreme corners of the hex, and when force is applied those corners deform — that is the mechanism by which nuts get rounded. An adjustable spanner is no better, because it flexes open under load and does the same thing from the outside. Once a fastener is rounded, the remaining options are a stud extractor, a chisel, welding a nut on, or a grinder, and every one of them is longer and messier than simply having the right socket.

That is the argument for buying the odd sizes rather than only the popular ones: they cost very little, and each one prevents a specific job from going badly wrong.

The socket is drop forged from fine chrome vanadium with a matt chrome finish. Forging flows the internal grain of the steel around the hexagonal form rather than cutting through it, which is what keeps unbroken metal running through the six corners where all the stress in a socket concentrates. Chrome vanadium is the standard hand tool alloy: chromium for hardness and wear resistance, vanadium for grain refinement and toughness.

The buyers are commercial vehicle and plant mechanics, agricultural and plantation engineering, industrial and factory maintenance, hydraulic and machinery fitters, and hardware dealers who keep the sizes their customers cannot find elsewhere.

Two rules that apply to every socket in the range. Seat it fully before applying force, since a socket bearing on the tips of the hex is how fasteners get rounded. And never fit a chrome hand socket to an impact wrench — plated hardened chrome vanadium is brittle under impact hammering and can crack and throw fragments. Impact tools take black chrome molybdenum impact sockets. Message us on WhatsApp for a price, or for a group of the awkward sizes.