Secchi Disc with Holding String Subcategory_Stopcocks sized for side-by-side strength comparison

sized for side-by-side strength comparison against the chrome-steel cylindrical series of similar dimensions

and a bar magnet for both electrostatic and circuit investigations

Regulated dual-output power supply showing independent LED readouts of voltage and current

supplying the plastic-coated counterpart to bare copper for circuit wiring where exposed conductor must be avoided

dispersion

Secchi Disc with Holding String Subcategory_Stopcocks sized for side-by-side strength comparisonLowers into ponds, lakes, or streams on its holding string until the alternating black and white quadrant pattern disappears, giving a direct field reading of water clarity.