Number Bugs 1-20 create multi-coloured number bugs which slot together easily. The plastic body segments have numbers on one side and are blank on the reverse to enable the teacher to hide a number for the child to identify. The heads are 50mm (to top of antennae) x 40mm wide and the body segment is 35 x 35mm. Ideal for developing fine motor skills, sorting & counting and numeracy. Contents: 4 caterpillar bug heads, 20 body segments 1-20 (number on one side, and blank on the reverse)