Adjustable devices designed to securely hold two objects together or to hold an object in place; used with standard-taper and ball-and-socket joints, glass and tubing assemblies, and with ring stands. Available as plastic joint clips, stainless steel pinch clamps, and taper clips.

A laboratory clamp is an essential piece of equipment used to support and secure labware and other laboratory apparatus such as flasks, reaction vessels, tubing, thermometers, probes, columns, funnels, and overhead stirrers.

Some laboratory clamps consist of a shaft and boss head, secured with hand-tightened thumbscrews, knurled nuts, or wingnuts onto a supporting rod, stand or scaffold. They may also include two- or three-pronged, adjustable closing jaws designed for gripping objects safely and securely.

Laboratory clamps are constructed of metals such as stainless steel, nickel-plated zinc, plated brass or diecast aluminum alloy for enhanced chemical, heat, and corrosion resistance. However, some components such as the adjusting screws may be made of plastic, and the prongs may also be lined or covered with cork, plastic, glass-fiber, or rubber for enhanced grip with minimal damage or breakage.

Laboratory Clamp Styles and Designs
• Universal, general-purpose clamps that are fully adjustable for accommodating and securing a wide range of items of different sizes such as columns and thermometers
• Retort clamps for securing round-bottom flasks and similar glassware
• Fork clamps for securing and supporting cone-and-socket ground glassware joints
• Three-prong extension clamps, sometimes available with spring-loaded jaws, for holding irregularly shaped or outsized objects
• Specialized clamps for securing burettes and condensers or reaction vessels
• Chain clamps, which incorporate a circular, adjustable chain loop to hold cylinders and beakers