Knipex 87 01 250 Cobra Water Pump Pliers (250mm)

By Knipex · Model: 87 01 250 · Tools

German-engineered 250mm water pump pliers with push-button adjustment and self-locking jaw that grips harder under load.

One-hand push-button adjustment for instant jaw width setting
Self-locking jaw grips harder the more force is applied
Box-type joint provides extreme stability and long service life
Works as pipe wrench, nut wrench and adjustable pliers in one
Non-slip plastic coating handles for secure grip
Chrome vanadium electric steel, oil-hardened for durability

Overview

The Knipex Cobra 250mm is arguably the best-known hand tool in the professional UK trades market. Its self-locking jaw mechanism is demonstrably superior to traditional adjustable pliers, and the price point puts it firmly in easy-purchase territory for any tradesperson.

In-Depth Look

The Knipex Cobra is one of those tools that sells itself through word of mouth. Ask any plumber, electrician, or mechanic in the UK what their most-used hand tool is, and the Cobra 250mm comes up with remarkable frequency.

Self-Locking Jaw

The defining feature of the Cobra is its self-locking jaw mechanism. A compound lever action means that as you apply force at the handles, the jaws clamp tighter against the workpiece — not looser. Unlike traditional water pump pliers where the jaws splay open under heavy torque, the Cobra holds its grip. This produces less fastener rounding on hexagonal fittings and a far more confident grip on round sections of pipe, cable glands, and compression nuts.

Push-Button Adjustment

The one-hand push-button adjustment is a genuine time saver. Instead of wrestling with a traditional slip-joint that requires two hands to adjust and often jumps positions under light pressure, the Cobra’s push-button mechanism releases cleanly, slides to the width you need, and locks precisely. Jaw width can be adjusted to any position, not just fixed increments, which means it can grip unusual sizes that a fixed-slot mechanism would skip past.

Box Joint Durability

The box-type joint that connects the two plier halves is stronger and more wear-resistant than the open rivet joint used in cheaper water pump pliers. Open rivets loosen over time with heavy use, introducing slop into the mechanism. The Cobra’s box joint maintains its precision for the lifetime of the tool — which is typically measured in decades of daily professional use.

Size Range

The 180mm Cobra suits fine work inside electrical panels and for smaller compression fittings. The 250mm is the most versatile all-rounder for plumbing and general trade use. The 300mm handles large pipework, basin taps, and high-torque applications. Many tradespeople start with the 250mm and subsequently add the 180mm for tight-access work.

Verdict

The Knipex Cobra 250mm is one of the best-value tool investments any tradesperson can make. It replaces multiple tools, lasts decades, and performs with precision that cheaper alternatives cannot match.

Specifications
Overall Length	250mm (10")
Jaw Capacity (nuts)	Up to 46mm
Jaw Capacity (pipes)	Up to 50mm
Weight	390g
Material	Chrome vanadium electric steel, oil-hardened
Joint Type	Box joint with push-button adjustment
Origin	Solingen, Germany

Who It's For

Plumbers and HVAC engineers working with pipework and fittings
Electricians needing an adjustable gripping tool for conduit and cable glands
General builders and mechanics needing one versatile plier

Pros & Cons

Pros

Push-button adjustment is faster and more precise than slip-joint designs
Self-locking under load means rounded fasteners are far less common
Exceptional build quality with a lifetime of service life
Accessible price point makes it an easy purchase decision

Cons

250mm size may be too large for some electrical cabinet work
Non-slip coating can wear over time with heavy use
Not ideal for very fine precision work on delicate fittings

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