[REUSABLE SCUM DISC] - Don't throw your hot tub sponge scum ! When it gets bogged down with muck, simply squeeze out the oil, rinse out the sponge, and use it again. [ IMPROVE FILTRATION SYSTEM] - By absorbing inanimate scum and lotion/oil, the sponge helps to reduce the load on the filtration system and filter, maximizing its service life, minimizing maintenance costs and saving you time. [EASY USE] - Just throw in the oil-absorbing sponge and let the filter pump run for a while, let them float freely (occasionally flip) to complete the cleaning of the pool.By absorbing all the scum, no scum lines will form on the tiles and/or the walls of the pool/ spa / hot tub. [WIDE USE]- Oil-absorbing sponges help eliminate the inanimate scum in the swimming pools, hot tubs, jet baths, massage bathtub and spas. [TIP] - It is recommended to have two Oil Absorbing Sponges floating around the water for best results.Absorbs multiple times its weight in oil, slime, grim and other types of scums. It is recommended to have two Turtle Oil Absorbing Sponges floating around the water for best results. Colour: white Material: sponges Size: 115 x 115 x 30mm Package Contents: 50 x Oil absorbing sponge Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.