Medical grade borosilicate glass is one of the safest materials for internal use and extremely resistant to breaking. It is also dishwasher safe, boilable, frictionless, compatible with any lubricant, can be chilled or heated, non-porous, hypoallergenic, phthalate free, latex , long-lasting, shipped with storage pouch, artistically designed and hand-made. Borosilicate glass is one of the safest materials. Extremely resistant to breaking, dishwasher safe and compatible with any lubricant. You can freeze or boil the toy to then use in temperature play! Non-porous, hypoallergenic, phthalate & latex free. These toys are handmade, so they may have slightly different sizes to the dimensions shown. Shipped with a padded, plush storage pouch.