Double Concave Glass Lens, 50mm Diameter, 100mm Focal Length, 16.5mm Thick Subcategory_Alternative Energy Hand-painted animal cell model reveals

Hand-painted animal cell model reveals organelle structures

and steel in a snap-top case

three interchangeable scales

applying tension to material strips until failure for breaking-strain and tensile-strength measurement in materials-science work

expanding and closing to suit different optical-component sizes on a single bench-mounted holder

Double Concave Glass Lens, 50mm Diameter, 100mm Focal Length, 16.5mm Thick Subcategory_Alternative Energy Hand-painted animal cell model revealsDouble concave glass lens at 50mm diameter and 100mm focal length, a thick 16. 5mm blank with optically true surfaces, the diverging curvature producing virtual upright images for refraction work.