Capsules fit inside the flash battery compartment to help protect lens and electronics from humidity * Prevents damage and corrosion from harming your camera equipment * Keeps lens from fogging up * Fits all ReefMaster camera housings, and can also be used inside Sealife camera housing * Dimensions: 5.9 x 5.9 x 1.6 inches (WxHxD); weighs 1.3 pounds