RIDGID 31170 Model 1010 Non Telescoping Basin Wrench 3/8 1 1/4 inch

Amazon

Spring-loaded jaws of forged alloy steel provide fast, one-hand ratcheting Tension plug holds head in any position up to 90° angle Pipe capacity: 3/8 - 1 1/4" (10-32 mm) Nominal size: 10" (250 mm)

Zoro Tools

Forged steel jaws, spring loaded to easily grip nuts behind sinks and basins. The head can be positioned at any angle up to 90. Solid steel square section handle with sliding tommy bar.