Tongue-and-groove pliers are adjustable pliers used to grip, turn, hold, loosen, or tighten objects of different sizes. They are especially common in plumbing because the jaws can open wide enough to grab pipes, drain fittings, slip nuts, hose connections, and other round or irregular parts.
Many homeowners call them Channel Locks, but Channellock is actually a brand name. The generic tool name is tongue-and-groove pliers, channel-type pliers, or sometimes water pump pliers.
How Tongue-and-Groove Pliers Work
Tongue-and-groove pliers work by using an adjustable pivot. One handle has a “tongue” that slides into different “grooves,” letting the jaw opening get larger or smaller depending on what you need to grab.
Most versions have:
- Serrated jaws that bite into round or slippery surfaces
- Angled jaws that make it easier to reach pipes and fittings
- Long handles that give you leverage
- Multiple adjustment positions for different pipe and fitting sizes
Once the jaws are set, you squeeze the handles to clamp down on the part. The tool does not automatically lock like locking pliers, so your hand pressure controls the grip.
What Tongue-and-Groove Pliers Are Used For
Tongue-and-groove pliers are one of the most useful general repair tools a homeowner can own.
Common uses include:
- Loosening or tightening sink drain slip nuts
- Holding a pipe or fitting while another tool turns a nut
- Removing stuck hose connections
- Gripping round plumbing parts
- Tightening large plastic nuts under a sink
- Holding irregular parts that do not fit a normal wrench
- Light demolition or repair work where a strong grip is needed
They are especially helpful when the part is too large for regular pliers or when the shape is not a clean hex nut.
How to Choose Tongue-and-Groove Pliers
For most homeowners
Use a 10-inch pair of tongue-and-groove pliers. This is the best all-around size for sink drains, general repairs, and most homeowner plumbing tasks.
For tighter spaces
Use a 6-inch or 8-inch pair. These are easier to use under sinks, inside cabinets, or around small supply line fittings.
For larger plumbing work
Use a 12-inch pair. The longer handles give more leverage and the jaws open wider, which is helpful for larger drain fittings, cleanout caps, and some outdoor hose or irrigation parts.
For delicate finishes
Use smooth-jaw pliers, soft-jaw pliers, or wrap the part with a rag or painter’s tape before gripping. Standard serrated jaws can scratch chrome, polished brass, painted finishes, and plastic.
For faster adjustment
Use push-button tongue-and-groove pliers. These let you adjust the jaw opening more quickly and can be easier for beginners because they are less likely to slip out of position.
Tongue-and-Groove Pliers vs Adjustable Wrench vs Pipe Wrench
| Tool | Best For | Not Best For |
|---|---|---|
| Tongue-and-groove pliers | Round fittings, slip nuts, gripping irregular parts | Finished surfaces that can scratch |
| Adjustable wrench | Hex nuts and bolts with flat sides | Round pipe or soft fittings |
| Pipe wrench | Heavy steel or iron pipe | Chrome, copper, brass, plastic, or decorative fixtures |
A good rule: use an adjustable wrench on flat-sided nuts, tongue-and-groove pliers on larger odd-shaped fittings, and a pipe wrench only when you need serious bite on rough pipe.
How to Use Tongue-and-Groove Pliers
Open the jaws wider than the part Adjust the pivot so the jaws can fit around the pipe, nut, or fitting.
Set the jaw angle Try to position the jaws so they bite evenly and do not slip off the part.
Grip firmly Squeeze the handles together. If the pliers feel too open or too closed in your hand, move the pivot to a different groove.
Turn slowly Apply steady pressure. Do not jerk the tool unless you are doing demolition.
Protect finished parts If the part is chrome, brass, plastic, or painted, add a rag or tape before gripping.
Common Mistakes
Using them on chrome without protection
The teeth can leave deep scratches.Using them on a hex nut instead of a wrench
They can round off the nut. If a nut has flat sides, use an adjustable wrench or the correct-size wrench.Over-squeezing plastic fittings
Plastic slip nuts can crack if you crush them.Using one pair when you need two tools
Many plumbing jobs need one tool to hold the fitting still and another to turn the nut.Calling every pair “Channel Locks”
Fine in conversation, but for SEO and shopping, the better term is tongue-and-groove pliers.
Recommendations
Overall DIY Recommendation
10-inch tongue-and-groove pliers
Best for:
- Sink drain repairs
- General plumbing
- Hose connections
- Everyday homeowner repairs
Why this size works:
- Big enough for common plumbing fittings
- Small enough to use under sinks
- More versatile than very small pliers
- Affordable and easy to store
Best Value Recommendation
10-inch and 12-inch tongue-and-groove pliers set
Best for:
- Homeowners who expect to do more plumbing work
- Sink repairs, toilet repairs, outdoor hose work, and appliance connections
- Situations where you may need one tool to hold and another to turn
Why it’s better:
- Gives you more range
- Lets you use two pliers at once
- Reduces the temptation to force one undersized tool
Delicate Finish Recommendation
Smooth-jaw or soft-jaw pliers
Best for:
- Chrome fixtures
- Shower heads
- Faucet parts
- Plastic drain fittings
- Decorative plumbing finishes
Why it matters:
- Regular serrated jaws grip well but scratch easily
- Smooth or padded jaws reduce visible damage
Fixers Club Tip
If a fitting is not moving, stop before you crush it. A stuck plastic nut, corroded hose connection, or old shutoff valve can turn into a bigger repair quickly. Send a photo to Fixers Club and a pro can help you decide whether to use more leverage, add a second backup tool, apply penetrating oil, or call a plumber.