Fieldsheer’s® women’s Proton Heated Baselayer Shirt is an all-season favorite designed to be worn under a sweater, snow jacket, or other outdoor gear, with a sporty silhouette that allows it to be worn on its own. Powered by Powersheer™, the 7.4-Volt Lithium-Ion battery holds up to ten hours of power per charge delivering comfort no matter what nature throws at you and with a universal USB charging port. The subtle camouflage design adds a level of detail and sophistication to the front and back, while a 3/4 zip keeps the Proton Heated Baselayer Shirt securely in place. Integrated with our Mobile Warming® Technology, simply activate one of four heat settings with our proprietary Bluetooth® integrated MW Connect™ app. The Sweatsheer® liner draws moisture away from the body, providing lasting comfort without sacrificing mobility. The poly fabric blend offers mobility, comfort and performance, keeping you in the field and doing what you love longer.