This 1 - 5 Stair helps students with beginning counting and the concept of grouping ones to form numbers up to five. The Stair consists of five joined vertical grooves in which to fit Unifix Cubes. The Cubes can be locked into bars to illustrate the concept of whole numbers. The Stair is made of sturdy gray plastic with embossed numbers and measures 4 1/2" x 4 7/8". Cubes are not included.