[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 for 20–30 uses. [How to maintain them?] Clean and dry your skin before using. After using the gel sheets, stick them back to the cardboard. Gel sheets are consumables. Replace with a new sheet in the following cases: 1. When you noticeably feel a decrease in conduction performance, resulting in reduced effectiveness. 2. When it loses adhesiveness, the gel surface dries out, or there is damage or dirt that cannot be cleaned. How to use: The side attached to the white paper should be applied to the device 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 Note: Only the items listed above are included. Other products are not included. Lighting and display differences may cause slight color variations between the image and the actual item. Measurement may vary by +/- 1–3 cm.