Fabric is water resistant however, it is not waterproof.
There are so many fun colors to choose from, you can coordinate them with your outfits. Sensor Bands are a fun, stylish way to cover your CGM sensor, POD, or Neulasta. Comfortable, 4 way, spandex fabric, adds a layer of protection to your device. If you are headed to the beach, lake, or pool, be sure to take this with you. The compression band will help keep your device from floating away unexpectedly.
Measure, snugly, around your arm, where you will wear your device. DO NOT measure around your device, the sizes already accomodate fot this. You want this to fit snug, but to be comfortable. Order the size that fits your measurement, IE 8.75" order the X-small which fits 8"-9".