Safety Goggles - Indirect Vent Type_Tall Form formed to measure atmospheric pressure

formed to measure atmospheric pressure through mercury or indicator-fluid column rise

and 400 ppm

the slim half-disc geometry letting beams enter the curved face along its radius for clean refraction-angle and TIR observations

deliberately using non-standard graduations to build empirical reasoning

the longest focal value in the 50mm convex line giving the gentlest divergence and largest virtual image

Safety Goggles - Indirect Vent Type_Tall Form formed to measure atmospheric pressureGeneral purpose googles with side ventilators. General purpose googles with side ventilators. Designed to protect eyes from chemical splash and dust.