One type has fixed jaws opening at right angles to the shaft handle. It is primarily used to remove supply nuts and hose coupling nuts on faucet spray attachments under worktables, sinks and lavatories.
The second type has spring tension pipe-gripping jaws that are reversible by flip-over on the end of drive shaft handle. It will grip pipe nipples, odd sized supply nuts and jam nuts in hard-to-reach spots.
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Also known as a faucet wrench or a crowfoot faucet wrench.