Standard Rheostat, 8.5Ω, 5A Max Lab Supplies_Spring Scales and four rotary controls

and four rotary controls

and spectral-line work

where colored liquid in a U-shaped section shifts measurably as air blown through a constricted glass tube creates pressure differences

Fully enclosed EDM-80 moving-coil DC milliammeter measuring 0-500mA at plus-or-minus 2

closing when a magnet is brought near to introduce magnetic-actuated switching alongside hand-operated switches

Standard Rheostat, 8.5Ω, 5A Max Lab Supplies_Spring Scales and four rotary controlsStandard rheostat at 8. 5 ohms and 5A with oxidized constantan winding on a vitreous enameled steel tube, the lower resistance higher current option in the standard rheostat line.