[What's it for?] Hydrogel gel sheets. accessory for all Abdominal Belt. AB Trainer. Waist Trimmer Belt. ABS Toner Body . ABS Stimulator.[How long can the gel sheets last?]The gel pad need to be replaced regularly. every pad could 20-30 .[How to maintain them in a ?]Clean/dry your skin before using; Stick them back to the cardboard after using this Gel Sheets PadGel sheets are consumables.replace with a new sheet at the following :1.Obviously feel the conduction performance decreased.cause decreased strength.2.When it loses its adhesiveness. the adhesive surface(gel)dries out or is gouged or dirt/grime that cannot be removed exists.How to use:The side attached to the white paper should be attached to the gel pad.The side attached to transparent film should be attached to the skin.colour: blueMaterial: hydrogelsize: 4 * 6cmPackage Contents: 48*Abs Trainer Replacement Gel SheetOnly 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.