[What's it for?] Hydrogel gel sheets, accessory for Abdominal Belt, AB Trainer, Waist Trimmer Belt, ABS Toner Body, ABS Stimulator. [How long can the gel sheets last?] The gel pad needs to be replaced regularly; each pad can last 20–30 uses. [How to maintain them?] Clean and dry your skin before using. After use, stick the gel sheets back to the cardboard. Gel sheets are consumables. Replace with a new sheet in the following cases: 1. When you noticeably feel decreased conduction performance or reduced strength. 2. When it loses adhesiveness, the gel surface dries out, or there are gouges or dirt that cannot be cleaned. How to use: The side attached to the white paper should be placed on the gel pad. The side attached to the transparent film should be applied to the skin. Color: Blue Material: Hydrogel Size: 4 x 6 cm Package Contents: 48 x ABS Trainer Replacement Gel Sheets Only the above package content is included; other products are not included. Note: Lighting and different displays may cause slight color differences between the image and the actual item. Measurement allows an error of +/- 1–3 cm.