SI Manufacturing CaddyStack Electricity KitA complete classroom set of basic electrical components designed with both quality and economy in mind. The Electricity Teacher's Guide contains activities for designing and building simple circuits, switches, series and parallel circuits, motors and buzzers. Kit includes: 15 economy bulb holders, 15 economy switches, 15 miniature bulbs, 15 battery holders, 15 "D" cell batteries, 3 packages of 10 wire connectors, 2 motors, 2 buzzers and a teacher's