a) Oxygen pressure indicator b) Certificate:ISO9001:2008 c)Bourdon tube: Brass or bronze ... .Accuracy:Normal Grade 2.5, 1.5 1.0 0.05%accuracy 3.Diameter of outside:40mm=1.5'',50mm=2 ... 7.Temperature:-10~70°C 8.Certification:ISO9001:2008 9.Dial plate:Single and dual scale (psi, kpa, mpa, bar, kg ... the load measurement limit 3/4. Bourdon Tube Oxygen pressure indicator