Fan Cart, weight: 0.5 lb., dimensions: 6in x 5in x 5in, two AA size batteries, propeller delivers a thrust of about 88mN, accelerating the cart at 0.4 m/s2
Ray box, simple, safe and sturdy source of projected light for many classic optics experiments, produces parallel convergent rays across a plane horizontal surface and the rays are intense enough to be traced in natural light. Built in solid aluminum extrusion casing, 100-240V 50/60 Hz