2.5" Closed Ring with Boss Head Clamp Material_Polypropylene Wooden-framed abacus with five steel

Wooden-framed abacus with five steel wires and 20 beads per wire on a 13

Five-hundred-milliamp DC scale on a 315x115mm laminated panel with sealed shunt

One-volt DC scale on a 315x115mm laminated panel with sealed multiplier

the half-disc geometry letting light enter perpendicularly through the curved face for Snell's law and TIR ray-tracing experiments

and small labware a stable flat surface during retort assemblies

2.5" Closed Ring with Boss Head Clamp Material_Polypropylene Wooden-framed abacus with five steelIntegrated open boss head pairs with a 2. 5 inch closed ring on this plated mild steel retort accessory, accepting vertical rods from 5 16 to 5 8 inch for quick ring placement.