Set of 15 different cylinders (pegs) ranging in density from 0.5 to 9 g/mL. Includes acetal, acrylic, aluminum, brass, copper, CPVC, HDPE, maple, nylon, PETG, phenolic resin, polystyrene, PP, PTFE, and PVC. Large cylinder volumes (7 to 18 mL) increase accuracy of density determinations. Peg color and size help teachers identify them easily. Instruction manual provides suggested activities as well as descriptions of each material and its use.