Metric Diameter Gauge Tubing Sizer
By Bel Art Products
A handy metric diameter gauge that will end doubt about inside or outside diameters. The gauge measures glass and plastic tubing, connecting pieces, rods, test tubes, etc. between 1.5 and 16mm. Holes on one side measure O.D.; pins on the other side measure I.D. Keep one with your tubing and one with your culture, centrifuge or test tubes. Made of autoclavable polypropylene.