This unit is safer, faster and more accurate than mercury based thermometers. It produces oral readings in approx 1 minute and keeps reading in the memory for the next use. Comes complete with long life lithium battery. The large LCD display makes it easy to read the temperature. The large, flat shape of the probe enables it to be held stably in the armpit. This provides a more usable design for everyone, from small children, who can't sit still, to older people, who may have trouble reading a small display.