Long Hex Key Wrench (4x10pcs)

It is the key for M5 socket head cap screws, and those are all over motorcycle engine covers and brackets, vehicle interior and trim fixings, small hydraulic and pneumatic fittings, machine guarding, electrical panel gear, furniture frames, and imported equipment of every kind. On a motorcycle in particular it is the size a mechanic reaches for constantly.

The point worth making at 4mm concerns what is on the other end of the screw. An M5 cap screw made to a normal grade is considerably stronger than the aluminium casting or the plastic boss it is very often threaded into. That mismatch is the whole story of stripped threads. The screw will happily accept more turning force than the housing can hold, and because the housing gives way gradually there is no sharp warning before the thread lets go. When a mechanic says a bolt sheared, more often the casting stripped.

A long key makes this easier to do, not harder. The extra arm is more leverage, and leverage is the one thing a small screw in soft metal does not need. So the honest advice with this key is to use the reach and ignore the leverage: run the screw down until it takes up, feel it seat, and stop.

Where the pattern earns its money is access. Engine covers, guards and panels are exactly the places where a screw sits recessed, behind a fin, or under an edge that a short key cannot approach squarely. Approaching squarely is the thing. A key entered at an angle contacts the corners of the recess rather than the flats, and corner contact is how a socket head is destroyed.

Forged chrome vanadium, hardened and tempered.

The buyers are motorcycle and three wheeler workshops, vehicle technicians, machinery and equipment fitters, panel builders and electricians, furniture and shopfitting trades, and hardware shops supplying all of them.

If a thread has already stripped, do not simply put a bigger screw in it. We stock thread repair taps and inserts and can tell you which is right for the material.

The bracket in the catalogue name carries Harden's carton figure rather than the quantity sold. This is one 4mm key. Talk to us on 94 77 111 8880, ask about shop quantities, and we deliver island-wide.