Round Convex Glass Mirror, 75mm Diameter, 300mm Focal Length Subcategory_Weights and Masses Adjustable iris from closed to

Adjustable iris from closed to a 30mm maximum aperture inside a 3-inch black metal body

Used to supply rechargeable DC power for circuit experiments

Open-frame demo motor with two opposing coils on a spinning axle and 4mm banana inputs

Aluminum-nickel-cobalt bar magnets engineered for stable

sized to reconfigure the demonstration meter as a 0-1A ammeter for full-class viewing of student-built circuit currents

Round Convex Glass Mirror, 75mm Diameter, 300mm Focal Length Subcategory_Weights and Masses Adjustable iris from closed toLong focal 75mm convex glass mirror at 300mm focal length and ~1. 2mm thickness, the gentlest divergence in the 75mm convex line for the largest virtual reduced images.