1)water massage treatment 2)Oxygen-ion release and air purification ... can not only enjoy the water massage, but also the oxygen spa at your bathtub.With certificates of GS, ROHS, CE ... , LVD, EMC ,UL,SGS ,JET, SAA , etc. Main function:1) Jet water stream massage ... to plug: 2.8M Tourmaline (ION): Home whirlpool bathtub massager CE Rohs GS,PSE,UL certificates