The Omron Probe Covers for TH839S are disposable covers designed to fit over the probe of the Omron TH839S ear thermometer. The covers are intended to protect the probe from contamination and help prevent the spread of germs between uses. The pack contains 40 probe covers, which can be easily attached to the thermometer probe before each use. The covers are made of a soft, flexible material that is comfortable to wear and allows for accurate temperature readings. To use, simply remove a cover from the pack and slide it over the probe until it fits snugly. Take the temperature reading as instructed by the thermometer manual, and then dispose of the used cover. It is recommended to use a new cover for each use of the thermometer, especially when measuring the temperature of different individuals. Overall, the Omron Probe Covers for TH839S are an essential accessory for anyone who uses the Omron TH839S ear thermometer and wants to maintain proper hygiene and prevent the spread of germs.