Purple Molecular Model Atom, 2.2cm, 4 Holes, 10-Pack Lab Equipment and Supplies_Audio Visual Equipment Extended-range rheostat at 12 ohms

Extended-range rheostat at 12 ohms and 4A on a 200x44mm tube with constantan winding

75 inch shaft for chemistry apparatus connections

the f/1 geometry producing strongly converging beams for vivid magnification and real-image demos

the apex continuing the wedge-deviation series for systematic angle-versus-deviation comparison across geometries

Purple Molecular Model Atom, 2.2cm, 4 Holes, 10-Pack Lab Equipment and Supplies_Audio Visual Equipment Extended-range rheostat at 12 ohmsFour hole purple atoms in a 10 pack at 2. 2cm diameter, a standard kit spare for atoms forming four bonds in ball and stick molecular structures.