Two prong, adjustable clamp Integral bosshead Universal- clamp is ideal for use with straight sided glassware and apparatus such as burettes, tubes and flask necks Jaws are coated with nonslip vinyl Clamp measures 8" in length Universal, 2-prong single adjustable clamp with integral bosshead. Jaws are coated with nonslip vinyl for a secure hold. This clamp is ideal for use with straight sided glassware and apparatus such as burettes, tubes & flask necks. Can hold objects of 8-30 mm diameter. Overall length of clamp is 8".