The Ugears® STEM lab collection offers you an amazing opportunity to assemble two pieces of mathematical precision equipment: a mechanical Addiator and a Mechanical Multiplier and perform basic mathematical operations using the laws of mechanics. The Mechanical Addiator is an adding machine which lets you subtract and add numbers. Use a stylus to move gear racks marked with arrows and numbers from 0 to 9 to perform the simplest math tasks in a fun way! The Multiplier is a flat hinge device capable of performing binary operations.