Heavy-Duty heat resistant material.Firmness and size can be adjusted by the amount of water used Suction cups prevent booster seat from floating or moving of your hot tub seat. Suitable for all spas and hot tubs,comfortable and attractive for both adults and children, especially great to use in elders bath as a sort of booster seat. Heat resistant material for heavy duty. The resistance and the dimensions can be adjusted according to the quantity of water used. Package includes: 1* Cushion Or 2* Cushions. We will provide you with 24/7 fast reply if you have any questions.