Optically Worked Double Concave Glass Lens, 75mm Diameter, 150mm Focal Length Gifts Set of eight enlarged mitosis

Set of eight enlarged mitosis stage models that sequence chromosome condensation

Brass-knife single-pole single-throw switch on a durable plastic base

Compact metal-box convection demonstrator at 10 by 4 by 3 inches with two glass chimneys

Engineered with a higher spring constant than a classic coiled novelty spring

walls revealing fluid levels behind the depth-dependent pressure jets

Optically Worked Double Concave Glass Lens, 75mm Diameter, 150mm Focal Length Gifts Set of eight enlarged mitosisOptically worked double concave glass lens at 75mm diameter and 150mm focal length, the diverging curvature producing virtual upright images for refraction and beam spreading work.