Digital Luxmeter, economical solution for light measurements in a learning situations, the autoranging feature makes a one-button-and-done instrument, auto power-off conserves battery power, and other functions include MAX, MIN, and HOLD, Requires a 9V battery (not included)
Transparent Turbidity Tube, simple apparatus is used to determine the transparency of water in lakes, streams, oceans as well as other bodies of water, Contains: 60cm transparent turbidity tube, rubber stopper with Secchi disc, 20cm silicon tube, Hoffman's clip, steel
conductivity tester, handheld device provides a qualitative visual indicator of the conductivity of different solutions, acids or salts, Two brass probes can be touched to a solid substance, or immersed in a liquid, to show conductivity on green LEDs