Lifetime guarantee. Guarantees fast, accurate readings; Beeps when placed correctly; Signals when done. Safe for all ages. Oral, underarm or rectal use. Guaranteed accuracy: Only the Accu-Beep feature guarantees fast, accurate readings. Continuous beep confirms you are using the thermometer correctly; Lets you know the thermometer is properly positioned; Signals when done; Clinically proven to match glass thermometer accuracy. Easy to Read: Extra large night light display for easy reading. Added Safety: No glass to break, mercury-free. Easy to Use: Auto memory shows last temperature taken; Fast, one-minute temperature read-out; battery/storage case included; Automatic shut-off.