Unlike any other balance, this one makes it possible to physically show that -1 is less than 0.
Weights placed on the outer pans represent negative integers and those placed in the inner pans represent positive integers.
When you place a weight in each pan on one side of the center post, the balance remains level as (-1) + (+1) = 0.
Great for small group work, the balance comes with two plastic pans, four plastic canisters, a set of plastic weights and a Teacher’s Booklet.
Some assembly required.
Download: Instruction & Guides