Regnault's Hypsometer prop65 Cotton twin cord at approximately

Cotton twin cord at approximately 30 meters long

Sodium chloride lattice kit with 27 color-coded gray and green atoms plus 54 connectors for building the full cubic NaCl crystal structure in three dimensions

and logic-circuit demonstrations

paired with a 13 mm curved enamel-coated steel blade for portable benchtop and laboratory measurement tasks

Used to read the microampere-scale currents found in photodiode and transistor-bias circuits

Regnault's Hypsometer prop65 Cotton twin cord at approximatelyDouble walled copper cylinder hypsometer at 34 by 6cm on a steam boiler, with thermometer tubulure and glass manometer for calibrating thermometer upper fixed points under steam.