ring spanner BrE
box end wrench AmE

The most common shapes are called open-ended spanner and ring spanner.

Metal ring spanners not.

The only types of spanner you are not likely to need in plumbing are ring spanners and socket spanners.

Erm Paul wanted ring spanners?

Some screwdrivers have an in-line nut at the top of the blade, adjacent to the handle, so that a ring spanner or open wrench can be used to increase the applied torque.

Ratcheting box end wrenches can often be employed in the same application but will nearly always be significantly wider.