Big Strong Tubes (9/16″ diameter) are super tough and can take very aggressive chewing. They are the strongest, longest lasting chews that chubuddy makes. Give your child a better choice and save clothing, pencils, toys and other things from getting chewed up. Big Strong Tubes are made of BPA-free, pthalates-free, lead-free, PVC-free, latex-free, non-toxic materials. They are top rack dishwasher safe. Increase focus, attention, and allow your child to self regulate in a discreet manner. Big Strong Tubes on navy tether holder with snap hook clip allows your child to keep the tube clipped to their shirt collar or shoulder for quick and easy access. Chubuddy stands behind all strong tubes with our excusive 90 day, no-chew-thru warranty. We want you o be completely satisfied with your purchase and we stand behind our products.