Drop GoPro inserts into sides of camera housing to prevent fogging in cold and humid environments. Inserts will last for approximately 4 uses. To dry out and reuse, heat inserts on a pan in oven at 300°F for 5 minutes. Store in an airtight bag. Package includes 3 sets of anti-fog inserts and Humonitor® to confirm that desiccant is active. Compatible with all HD HERO original and HD HERO2 Professional Cameras. Made in the USA.