With all the colds and flu going around this is a great device to carry in your purse or pocket. And it's indispensable when you have to use public rest rooms. The portable scanner instantly disinfects doorknobs, computer keyboards, faucets, phones whatever you have to touch that every body else in your office, home, public places is using. Wave it over the item and it kills 99.9% of germs in seconds. Why is it that these products never kill 100% of germs?