12Pcs Double Open-end Spanner Set

An open jaw slides onto a fastener from the side. That sounds minor until you meet the situations where it is the only option: a nut on a threaded rod with the rod running past it, a fitting on a pipe, a fastener under a bracket where nothing can be dropped over the top, a union between two lines. A ring spanner has to go over the end of the fastener and in all those cases it cannot. The open end can.

It is also fast. Off, quarter turn, back on, and because the two ends carry different sizes each spanner covers two fasteners.

The honest limitation has to be stated because it is the reason both patterns exist. An open jaw grips only two faces of a hexagon, and under high load the jaw splays slightly — which puts the load onto the corners of the nut and rounds them. So an open-end spanner is the tool for fasteners that are already moving, and the wrong tool for one that is seized. If you have a choice, crack it with a ring spanner or a socket and finish with this.

The pairings run 6x7, 8x9, 10x11, 12x13, 14x15, 16x17, 18x19, 20x22, 21x23, 24x27, 25x28 and 30x32mm — twelve spanners covering twenty-four sizes from 6 to 32, which is a genuinely complete spread including the awkward 21, 23, 25 and 28.

The material is chrome vanadium steel with a matt chrome plated finish, chromium giving the hardness and wear resistance that keeps a jaw from opening up over time, vanadium giving toughness.

The buyers are plumbers and pipe fitters, vehicle and machinery mechanics, agricultural and plant workshops, maintenance engineers, and hardware dealers.

Seat the jaw fully before pulling, and pull rather than push. Ask us on WhatsApp for a price, or for the double ring set alongside.