Features: Rack and pinion raising mechanism with collar lock and safety ratchet pawl, Adjustable tension assembly, Elevation tube has a 2.687-20 thread which allows for various adapters and assessors as well as custom attachments to be easily interchanged, 3 swivel casters with rubber tires, and Heavy duty lift locking mechanism raises and lowers stand on casters for mobility. A U.S. standard 3½” x 8” thread is machined in the head for instrument attachment. the column is hollow to permit downward sighting, with a clear 2.0” diameter aperture. These stands are provided with rubber shock bumpers and a shock-resistant plastic thread cap. The floor space required for both stands is 32½” x 37½”. Available in a low movable stand– 24″ to 41″ (WK-59-2310) and a high movable stand– 40″ to 73″ (WK-59-2320); shown right. Net weight: low stand is 138 lbs.; high stand is 160 lbs. Shipping weight: low stand is 198 lbs.; high stand is 220 lbs.