Best locking pliers

Klein’s 38602 is my top pick because it covers the widest range of plumbing work in one tool. Klein lists its jaw capacity at 2 inches. That’s wide enough for 1-1/2 inch copper, and 1-1/2 inch steel pipe just fits. That covers the drains, mains and fittings you’ll grab on most house jobs.

The curved jaws are the classic shape for round work. Klein says they grip a large variety of objects, and the hardened teeth give high torque on the workpiece. On a pipe or a round nut, a curved jaw touches at more points than a straight one, so it’s less likely to slip.

Klein changed two things that bother people about older locking pliers. The size is set with a thumb knob instead of a plain screw, so you can dial it in without looking. And the handles release without a separate lever, which Klein says keeps the tool pinch free.

That release matters in a cramped spot. On a classic locking plier, the release lever can snap shut on a finger. Here you just pull the handles apart.

Klein’s data sheet lists the overall length at 9.7 inches, the jaw at 1.59 inches long and half an inch wide, and the weight at 1.36 pounds. The grips are molded TPE in Klein’s orange and black, and the steel has a rust preventative coating.

On a plumbing call, this is the plier I’d clamp on a fitting while I break the joint next to it. The 1.59-inch jaw is long enough to hold a 3/4 inch tee by its body. It’s also the one to lock on a rounded hex once a wrench has slipped twice.

Klein covers its hand tools for the normal life of the tool, with proof of purchase from an authorized Klein distributor. Keep the receipt and confirm the seller if you plan to claim it. If you only buy one locking plier for plumbing, make it this one.

KNIPEX’s 41 04 250 is the heavy hitter here. KNIPEX calls it a heavy duty model and says it holds round, profile and flat material securely. The high clamping pressure comes from the toggle lever action, KNIPEX says.

KNIPEX lists the clamping width at 40 mm on round work, 30 mm on hex and 20 mm on square. In inches that’s about 1-9/16 inches round. It wraps 1 inch steel pipe and 1-1/4 inch copper, but not 1-1/4 inch steel.

It also has a wire cutter, which KNIPEX rates for medium-hard wire up to 3.0 mm across. That’s handy for snipping tie wire or a hanger strap without reaching for another tool.

The adjustment screw and release lever work the way a classic locking plier does: set the size with the screw, squeeze, and pop it open with the lever. KNIPEX says it works one-handed.

Where would a plumber use it? Clamping threaded rod while you cut it, holding a strap or bracket steady while you drill it, or locking on a round stem that won’t turn. KNIPEX’s own photos show it holding small tube and angle stock.

At 517 grams, it’s lighter than the Klein 38602 at the same 10-inch length. That’s a fair trade for the smaller opening if most of what you clamp is under 1-1/2 inches across.

KNIPEX’s data sheet lists the pliers as galvanized, 250 by 65 by 17 mm, and 517 grams. The jaws are marked chrome vanadium in KNIPEX’s own photos, and the sheet carries KNIPEX’s “Made in Germany” line. The Amazon title calls these round jaws, and the photos show curved, toothed jaws with the cutter behind them.

KNIPEX Tools LP gives the original buyer in the US and Canada a lifetime limited warranty against defects. A claim needs proof of purchase and a return authorization number from KNIPEX.

KNIPEX’s 40 14 250 has a lower jaw that pivots. KNIPEX’s Amazon listing says the jaw adjusts automatically to whatever you’re gripping. On a hex nut, that should let both jaws sit on the flats instead of biting at two corners.

The capacities show why. KNIPEX lists 45 mm on hex, 42 mm on square and 43 mm on round. That’s more than the 41 04 250 on every shape, and much more on square: 42 mm against 20 mm.

For plumbing, that makes it the plier for nuts. A big union nut, the nut on a pipe clamp, or a square-headed bolt on old hardware all sit better in a jaw that flattens out to meet them. On round pipe it still opens to 43 mm, about 1-11/16 inches.

KNIPEX says it’s a heavy duty model with an adjustment screw and a release lever, and that it works one-handed. The toggle lever action gives the high clamping pressure. The listing adds that the body is high-strength rolled steel and the jaws are forged chrome vanadium.

The trade-off is round work. At 43 mm, it opens a bit less than the Klein 38602’s 2 inches, so 1-1/2 inch steel pipe won’t fit. Up to 1-1/4 inch copper, it handles pipe and nuts in one tool.

It has no wire cutter listed, so keep a cutter or the KNIPEX 41 04 250 nearby for tie wire.

KNIPEX’s data sheet lists it at 250 by 67 by 20 mm and 600 grams, galvanized, with the “Made in Germany” line. That’s the heaviest 10-inch on this page, so it’s not the one to hold overhead all day.

KNIPEX Tools LP gives the original buyer in the US and Canada a lifetime limited warranty against defects. It’s the same warranty as the 41 04 250.

Klein’s 38601 is the 10-inch’s little brother, and the size is the point. Klein lists it at 7.9 inches long and 0.8 pounds, against 9.7 inches and 1.36 pounds for the 38602. In a sink base, those two inches decide whether the handles clear the cabinet wall.

Klein says the curved jaws make it ideal for clamping and turning round objects. That’s supply stops, compression nuts, P-trap slip nuts in metal, and short nipples. The jaw is 1.3 inches long, per Klein’s data sheet.

It shares the 10-inch’s best feature: the thumb knob. You can set the size with your thumb while your other hand holds the part, which is most of the job when you’re on your back under a sink.

The handles are molded TPE, and Klein lists a rust-resistant coating. Klein’s Amazon listing calls the handles lever-less and pinch free, while its data sheet describes a lever release design. Either way, it opens without a separate trigger to snag.

Where does the smaller size pay off? Holding a supply stop body while you turn the compression nut, gripping a short nipple behind a wall plate, or clamping a stem while you pull it. Klein lists the handles at 3.43 inches, which leaves room for your other hand and the wrench.

Klein lists the jaw capacity at 1.9 inches, nearly the same as the 10-inch. That’s more than I’d expect from a 7-inch tool, so I’d measure it on your own work before you count on it for pipe over 1 inch. It wasn’t a reason to drop it, since its job is small work in tight spots.

It carries the same Klein hand tool warranty as the 38602: the normal life of the tool, with proof of purchase from an authorized distributor.

IRWIN’s 6LN is the plier for places a curved jaw won’t fit. IRWIN says the long, straight nose gives easy access in narrow, hard-to-reach places. Think of a small nut behind a fitting, a clip on a valve stem, or a pin you need to pull straight out.

The release is IRWIN’s Fast Release design: one-handed and triggerless. IRWIN says it’s twice as easy to open. That counts with a long nose plier, since you often hold it at an awkward angle where reaching a trigger is hard.

Adjustment is a hex screw. IRWIN’s listing says tightening it adjusts pressure and draws the material together, for a more controlled release. Like the Crescent, you can use a hex key on it for a little more clamp once it’s set.

IRWIN says the teeth are hardened and made to grip from any angle, and the body is heat treated alloy steel. It has a wire cutter, so it doubles as a snip for small wire. The listing also says the grip zone is suited for high-temperature applications.

On plumbing work, I’d use it for the small, fussy parts: pulling a cotter pin from a valve linkage, holding a retaining clip while you seat it, or gripping the end of a cable. The nose gets in where a curved jaw’s width won’t.

It’s also a decent third hand on small work. Clamp it on a thin bracket or strap and it stays put while you drill or drive.

IRWIN doesn’t list a jaw capacity or weight for this one, so I haven’t put it in the pipe table. It isn’t a pipe tool anyway.

IRWIN backs it with its Lifetime Limited Warranty.

Crescent’s CLP5SETN-08 is the set I’d hand someone stocking a van from scratch. It has three curved jaw pliers, 5, 7 and 10 inches, and two long nose pliers, 6 and 9 inches. Crescent lists the models as C5CVN-08, C7CVN-08, C10CVN-08, C6NVN-08 and C9NVN-08.

Every piece has a wire cutter. Crescent says the curved jaws use an angled tooth pattern for a better grip and compound action for a powerful, non-slip locking grip.

The adjusting screw is knurled, so it turns easily by hand, and it has a hex key receiver on the bottom. Crescent says that once the first grip is set, you can tighten the pliers further by turning the screw with a hex key. The release lever has a plastisol dip for comfort.

Crescent says the pliers meet ASME B107.24 and B107.36, and that the maximum jaw opening matches ASME specifications. It doesn’t list a capacity number for each size, so I haven’t put them in the pipe table.

The set is alloy steel with a nickel plated finish that Crescent says resists rust and corrosion. Crescent lists the catalog weight at 4.06 pounds for all five.

The sizes cover the common plumbing range. The 10-inch is the pipe and fitting plier, the 7-inch works inside a cabinet, and the 5-inch fits where nothing else will. The 6-inch and 9-inch long noses reach small parts at two depths.

Five pliers in one purchase also means one warranty and one finish across the bag.

Crescent backs the set with a full lifetime warranty. On plumbing work, the 10-inch curved jaw does the pipe holding and the 6-inch long nose reaches a supply nut behind a vanity; the 5, 7 and 9-inch pieces fill the sizes between. If you already own a 10-inch curved jaw, a single long nose is the better buy.