Curved Jaw Lock-Grip Plier (10")

Chrome molybdenum is a genuine step up from the plain steel plate used on the standard locking pliers. It is the alloy used for impact sockets and highly stressed components, chosen because it is tough — it takes shock and heavy load and deforms rather than fracturing. In a locking plier that matters at the jaws and at the toggle pins, which are carrying the very high forces the over-centre mechanism generates.

The hardness figure of HRC 52-56 is what keeps the jaw serrations biting. Locking pliers are bought precisely because they grip what nothing else will — rounded nuts, seized fittings, damaged fasteners — and every one of those jobs is hard on the teeth. Soft jaws wear smooth and start slipping, at which point the tool has lost the one property it was bought for. Fifty-two to fifty-six is the range good cutting and gripping tools sit in: hard enough to hold an edge through years of biting into steel, tough enough not to chip.

The curved jaw is the pattern to choose for round work. The curve closes onto pipe, rod, bolt shanks and tube at multiple points around the circumference rather than pinching at two, so it grips without rolling off — which is exactly why the curved jaw is the most popular locking plier of all.

The 0-45mm opening range is unusually stated and useful, telling you exactly what the tool will take before you buy.

At ten inches, in double blister packaging, it is the standard workshop size.

The buyers are vehicle, motorcycle and plant mechanics, welders and fabricators, plumbers and pipe fitters, agricultural and machinery repairers, maintenance fitters, and hardware dealers supplying working trades.

The usual cautions apply and better steel does not soften them: hardened serrated jaws bite hard and will mark, score or crush plated, polished, thin-walled and finished work, and they round the corners of any nut you want to reuse. Set the screw so the jaws just close over the work — wound too tight, the toggle becomes very hard to release. Keep the screw and pivots oiled. Ask on WhatsApp for a price, or with the straight jaw version.