Fitting on 5/8" (16mm) support rods or smaller, this stamped steel clamp is plated for corrosion resistance and has a steel thumbscrew. The clamp is 9" (229mm)long by 3" (76mm) wide with a center distance 7-1/4" (184mm) between burettes. The unit is designed for use with burettes from 6mm to 16mm in diameter.