This warmer is designed to keep semen warm in the coldest of outside temperatures, protecting it from cold shock when performing A.I. procedures on winter days. This renders it extremely useful if there is a long distance between your cows and thawing devices, or if you are doing several A.I. procedures in a row and need to carry several A.I. guns outdoors for an extended period of time. The inside of the warmer can be maintained in a range from 77°-95° F (25°-35° C) by use of a rechargeable heating unit. When using the heating unit, it can maintain your semen at a safe temperature, regardless of temperature drops. Comfortably lightweight with an adjustable strap that can be hung from the shoulder, around the neck, or around the waist, providing easy access to A.I. guns while allowing you to keep your hands free when needed. Vinyl lining makes for a highly waterproof interior environment that’s easy to clean and forms a barrier against moisture and other contaminants and it has a pocket specifically for the rechargeable heating unit. Warmer includes battery-operated heating unit with a USB charger.