| This handy metric diameter gauge ends doubt about inside or outside diameters of glass tubing, connecting pieces, rods, test tubes, etc. Holes on one side measure O.D.; pins on the other side measure I.D. Measures any size between 1.5 to 16 mm. Made of unbreakable polypro-pylene, the gauge is 12 cm long, 5 cm wide, 1.2 cm high |