12-Tube Premium Wooden Test Tube Rack with Draining Pins, 9.3" Wide Pack Size_50 to dispense slowly (drop-wise)

to dispense slowly (drop-wise)

sized to mount alongside a tone generator for converting electrical signals into audible tones during sound-wave demonstrations

For timing physics

6A with constantan winding on a 300x44mm vitreous-enameled tube and a slide-bar carriage carrying a phosphor-bronze contact

4 inches long for chemistry and microbiology classroom stations

12-Tube Premium Wooden Test Tube Rack with Draining Pins, 9.3" Wide Pack Size_50 to dispense slowly (drop-wise)Polished hardwood test tube rack holding 12 tubes up to 25 mm across twelve draining pins, combining storage and inverted drying on a single 9. 3 inch wide base.