Eureka/Constantan Bare Wire, Model A Prong_4 supplied with heavy sliders whose

supplied with heavy sliders whose fine index marks support precise lens and mirror positioning

throttle position sensor

Momentary-contact push-button switch on a base with two 4mm terminals

5V replacement element so wet-cell demonstrations stay running once the original electrolyte loses charge capacity

Polished beech wood test tube rack with twelve vertical holes sized for tubes up to 28 mm diameter

Eureka/Constantan Bare Wire, Model A Prong_4 supplied with heavy sliders whoseSixteen SWG bare constantan wire on a 125g reel a copper nickel alloy with a low temperature coefficient that holds resistance steady across a wide temperature range.