Sensor cover is specifically designed for sensor or Freestyle libre sensor. Glucose monitor patch holds the sensor firmly to your skin for multiple days involving daily showers, swimming and sweaty exercises. Note: Skin allergies, please use with caution. Because of the long time tightly attached to the skin, the skin will be reddened when you tear it off. This is normal, please rest assured that it will return to normal after some time. The sensor covers waterproof and sweatproof, holding the libre 2 sensor firmly to your skin for 7 to 14 days. Sensor stickers can protect your sensor device when cycling, running, swimming, showering or doing other land and water activities. It's safe to go anywhere with CGM patches without worrying about damaged your libre sensors. Sensor patches are made of high quality latex-free breathable cotton fabric and strong wave-patterned adhesive, thin and comfortable, wear it and forget about it. No odour. Choose libre 2 patches that matches the colour you are wearing and it will look great. Sensor covers are no glue in the middle and the sensor will not be soiled by the glue. Clean your arm and keep it dry before installing the waterproof patch. This way the sensor patches will fit perfectly to the skin and stick more tightly. You can easily remove or replace the glucose patches if needed without pulling the Libre sensor. Package Includes - 40 pieces black diabetic sensor covers. We are committed to providing our customers with blood glucose sensor protection patches to solve the problem of sensors being easily dropped or damaged.