about this item Material: PVC. Load: 150 kg. Dimensions: approximately 40cm x 37cm x 15cm. The suction cups prevent the seat from floating or moving. Fills easily with a standard water gun or by jets into the spa. Its firmness and size can be adjusted according to the amount of water used. Comfortable and fashionable design. Product Description Color:As Picture Booster seat for spa and hot tub,waterproof inflatable massage mat for acupressure tub,spa seat cushion,back massage cushion,soft inflatable seat. Features: Suitable for all spas and hot tubs. Comfortable and fashionable design. Its firmness and size can be adjusted according to the amount of water used. Sturdy heat resistant material. Fills easily with a standard water gun or by jets into the spa. The suction cups prevent the seat from floating or moving. RemaASDue: Please ensure that when using these seats your spa water is chemically balanced. If out of balance, the product may not adhere to the surface. Item Type: Spa Cushion Material: PVC. Color: as the picture shows. Load: 150 kg. Dimensions: approximately 40cm x 37cm x 15cm. Contents: 1 x cushion. Note: 1. The color of the item may be slightly different from the product shown in the photos depending on your computer's display and brightness settings. Thank you for your understanding. 2. Due to manual measurement, there may be 1-3cm difference between the res and cs product dimensions listed.