The jumbo size of these number stamps makes it easy for little hands to grasp and use on their own. This set of numbers stamps is the perfect tool for practicing number recognition and simple equation building. This 33-piece set includes numbers 0-20, symbols and operation sign stamps made of durable plastic and rubber. Easy-to-hold stamps store in a clear, sectioned plastic case. Each stamp measures 1 ¼ each. Grades PreK and up.