1)Group up by 2 parts 2)With 3pcs dry battery,the dry battery can be replaced when they work out. (Dry battery can be used 5-6 hour when it put into product) 3)Smart and portable design,Cordless Convenience,one hand to easy operateConvenience,one hand to easy operate 4)Soft rubber material, anti-corrosion 5)2 vibration intensities 6)One button to easy operate 7)360 degree massage roller