What Does a Strap Wrench Do That Pliers Can’t?

Say a polished chrome shower head will not turn by hand. Toothed jaws, on pliers or a pipe wrench, can mark a polished finish or a plastic fitting, which is why some fixture makers tell you to protect the finish or call for a strap wrench. A strap wrench turns a round part with a flexible strap wrapped around it instead of teeth. This guide covers what that changes, where manufacturers’ own instructions call for one, when another tool may suit better, and how to size one. For the removal steps themselves, see our guide to installing a shower head.

What a Strap Wrench Does

A strap wrench has a handle and a flexible strap. You loop the strap around a round part, feed the free end through the handle, and pull, and the strap tightens as you turn. The grip comes from friction spread around the part rather than from teeth or hard jaws pressing at two points. Klein Tools says its Grip-It wrenches use a cam action to apply uniform, high torque, and RIDGID describes a strong woven nylon strap that grips tightly.

The same design sets its limits. The strap has to fit all the way around the part, and the strap and handle need room to move. Makers state capacity in different ways, as the sizing section shows.

Where Manufacturers Call for One

Follow the manuals for your own fixture and your own tool. These are examples from specific product sheets, not rules for every fixture.

• Kohler Rain showerheads. Kohler’s installation guide lists a strap wrench among the tools and says to tighten both the shower arm and the showerhead securely with a clean strap wrench when installing them.
• Kallista multi-function showerhead. This sheet says to tighten the shower arm with a clean strap wrench until it is oriented correctly. For the ball joint it says to use a clean wrench with the jaws wrapped in tape or a rag to protect the finish.
• Polished and plastic pipe and fittings. Klein’s page for the S12HB says that under normal conditions it will not scratch, damage or deform polished pipe and fittings, plastic pipe and fittings, oil and water filters, glass pipe, PVC conduit and polished shafts. It does not name chrome. RIDGID’s catalog recommends its strap wrenches for polished pipe and says two models come with a special strap for plastic pipe.

  

When Another Tool May Suit Better

• Nuts with flats. A wrench that engages the flats, such as an adjustable wrench or a basin wrench, is usually the more direct choice. See basin wrench vs. adjustable wrench.
• Threaded steel pipe where marks do not matter. A pipe wrench is the usual tool; our pipe wrench guide covers when to use a strap wrench instead.
• Filter housings. Follow your filter’s manual. 3M’s manual for its AP800 series housings says to use only the housing wrench supplied with the product when changing cartridges, and warns that overtightening can crack the housing. Other housings may differ.
• New connections that are meant to be hand-tightened. Delta’s shower mount sheet and hand shower sheet say to hand tighten and not to use a wrench or pliers, and Moen’s sheet for its shower diverter says to hand tighten and not to overtighten. Those are instructions for those products.
• When you would be adding leverage. Klein’s S12HB page says not to push or hammer the wrench, not to extend the handle, and to wear approved eye protection.

When You May Not Need to Buy One

Try a new connection by hand first. For taking an old head off, Delta’s shower mount sheet describes an adjustable wrench or pliers, with the shower arm held so it does not unscrew. The Kallista sheet’s tape-or-rag instruction is for tightening its ball joint, not for removing an old showerhead, but it shows the same idea of protecting the finish when a wrench is used. A strap wrench starts to make sense if you work on polished or plastic pipe and fittings often, if a finish would be costly to replace, or if your fixture’s instructions call for one.

Sizing and Clearance

Measure the outside diameter of the part, or wrap a string around it, mark the length and divide by 3.14, then compare with the maker’s stated capacity. Where a minimum is given, check it as well as the maximum: Klein’s page lists Grip-It models from 1-1/2 to 4 inches (6-inch handle) up to 3 to 10 inches (18-inch handle), and the S12HB covers 1-1/2 to 5 inches, so the current models listed there start at 1-1/2 inches or more.

RIDGID lists two capacity figures for each strap wrench, and they mean different things. RIDGID’s strap wrench page (archived copy) defines rated pipe capacity as the nominal diameter that can be correctly tightened, and actual O.D. capacity as the actual outside diameter the strap can accommodate. The second figure is larger. Do not choose on the larger figure alone: for pipe, stay within the rated capacity, and for other round parts the outside-diameter figure only shows that the strap fits, since RIDGID does not say how well the wrench grips at the top of that range.

On clearance, the makers publish handle and strap lengths but we found no figures for how much free space a wrench needs. You need room for the strap to go around the part and for the handle to swing a useful arc.

What Three Makers Publish

This is not a ranking. It shows what each maker states for pipe and fitting work.

What the documentation does not say. None of the three makers states a torque limit that we found, and none names chrome. Klein and RIDGID name polished pipe, and Klein names plastic pipe and fittings. Harbor Freight does not address polished, chrome or plastic surfaces, handle material or load rating, and notes that its specifications are approximate. RIDGID also lists P versions of the No. 2 and No. 5 with a strap for plastic pipe, and sells replacement straps. Availability changes, so check each maker’s current listing.

Frequently Asked Questions

Q: Will a strap wrench scratch chrome?

None of Klein, RIDGID or Harbor Freight names chrome. Klein lists polished pipe and fittings among surfaces it will not scratch under normal conditions, and Kohler’s Rain showerhead and Kallista sheets specify a clean strap wrench for tightening.

Q: Is it the right tool for a stuck shower head?

The sources we read do not say. Kohler’s instructions cited above cover installing and tightening a new shower arm and showerhead with a clean strap wrench, not freeing a seized one; for removing the showerhead to clean its screen washer, Kohler’s guide says to use a clean wrench and be careful not to mar the finish. For removing an old head, Delta’s shower mount sheet describes an adjustable wrench or pliers while the shower arm is held. If a head will not move, do not add leverage, since Klein warns against extending its handle.

Q: Can I choose by the biggest diameter listed?

Not on RIDGID’s figures alone. Compare the part’s measured outside diameter with the maker’s stated capacity, and for RIDGID keep within the rated pipe capacity when turning pipe.

Sources

Manufacturer documents read at the time of writing:

• Klein Tools, Grip-It Strap Wrench S12HB
• RIDGID catalog, strap wrenches (page 17) and RIDGID strap wrench page (archived copy)
• Harbor Freight, Pittsburgh rubber strap wrench set 69373
• Kohler, Rain showerheads installation guide 1141989-2 and Kallista multi-function showerhead sheet 1205966-2-B
• Delta shower mount sheet 75700 and hand shower sheet 69694; Moen instruction sheet INS10875
• 3M AP800 series whole-house filter housing manual