Dual scale, 660 - 810mm and 26-32 in. A good –quality instruments with Vernier scales reading to 0.05mm and 0.002in opel reflectors and adjustable cistern with white fiducially setting point; useful where the highest order of accuracy is not required with thermometer –10^oC to 50^oC x1^oC; on polished hard wood board. Bore of tube 6mm