The Ohaus CLS-WBATHZL Large Water Bath Clamp holds a variety of apparatus, including glass tubes and thermometers onto glass water bath walls. Built-in holder grips walls of varying thickness, up to 9 mm (0.35"). Knurled thumbscrew tightens jaws to hold objects firmly. Nickel-plated zinc construction. The CLSWBATHZL Large water bath clamp has a grip size range of 0 to 1.81", is supplied with non-slip vinyl sleeves and fiberglass covers for temperatures above 100° C.