Excellent quality, free-running pulleys. The sheaves are 30/40/50 mm in diameter and are made of rigid plastic. The block is constructed of metal with swivel hooks at the top and bottom. Color may vary.

Alkaline batteries provide a much longer life than conventional carbon-zinc batteries. They maintain a full-rated voltage for life. Panasonic is the ultimate battery for laboratory use. Pkg. of 2.

Handy, portable battery flashlight has a durable plastic outer casing. Exclusive diamond reflector provides a wider beam of light than most ordinary flashlights. Requires two “D” batteries (not included). No color choice. Pack of 12 flashlig..

The 4 ft. Slinky Spring with three times the normal length is ideal for demonstrating several fundamentals of wave motion. When the spring is extended to 30 feet, a lateral or longitudinal pulse can be observed in detail as it travels at the slower rate..

Longer and heavier, the spring demonstrates the effects of greater mass and of greater tension.

The 4 ft. slinky spring with three times the normal length is ideal for demonstrating several fundamentals of wave motion. When the spring is extended to 30 feet, a lateral or longitudinal pulse can be observed in detail as it travels at the slower rate..

A calorimeter with a double-walled cover will minimize heat loss. The inner and outer vessels are made of aluminum. The calorimeter has a stirrer and support for the inner vessel. Item is now interchangeable and can be used with or without electrici..

An inexpensive apparatus that demonstrates the principle of motion. A lever knife-edge clamp is mounted in a heavy balance support. A meterstick (not included) is easily attached on the knife-edge clamp.

Make a balance out of a meterstick with this metal clamp. The wire stirrup can be used for suspension of weights.

60° glass prism with 30 mm base and faces, for experiments in dispersion of white light into its spectrum colors, refraction of light, and demonstrating the principle of the prism spectrometer.