Plano-Cylindrical Concave Lens, -17 Diopter, 50 x 50mm Material_Bristle Two-speed ticker timer kit printing

Two-speed ticker timer kit printing 25 or 40 dots per second on paper tape via carbon discs

and tin specimens in a snap-top case for comparative mass-volume calculations

Dark-complexion life-size human torso with 13 removable organs including brain

75 inch wall thermometer

1 inches while the swivel boss head delivers 360-degree angular positioning and fits rods up to 18mm in diameter

Plano-Cylindrical Concave Lens, -17 Diopter, 50 x 50mm Material_Bristle Two-speed ticker timer kit printingPlano cylindrical concave lens at 50 by 50mm with 17 diopter power, the cylindrical concave curvature spreading light along a single axis for line focus and divergence demos.