Pieces made of innovative silicone material, in 5 colours, easy to clean, quiet and durable, which cling to all nonporous surfaces without leaving any residue. Promote hands-on discovery and a deeper understanding of concepts. You can write on the pieces with dry-erase markers. Are dishwasher safe, so you can sanitize them regularly and easily. Will cling like new after being wiped with warm, soapy water. Include a resource guide.