The Fieldsheer powered by Mobile Warming heating technology Backcountry Women's Heated Vest is Mobile Warming's new synthetic down puffer Heated Vest available in 2 color options and featuring a new low-profile 7.4-volt battery. With a Waterpell water-resistant nylon outer shell, and at its core, the tried and true Mobile Warming 7.4-volt heating system is enhanced with Primaloft synthetic down insulation. Primaloft is a down alternative made from recycled materials into ultra-fine insulative fibers. The Backcountry is stylish enough to wear on its own during day-to-day use, but light and amply compressible to also wear as a base layer under your favorite rain or snow Heated Vest. The Backcountry 7.4-volt heating system can provide heating temperatures ranging from 135F on high to 90F on low. On high, expect up to 2+ hours of heat, and on low it can heat up to 10 hours! Temperature control is simple with 2 ways to adjust the heat. First, the built-in waterproof touch control button. With a simple button push, it lets you choose from 4 instant heat settings with multi-colored LED indicator. Plus, theyincorporated Bluetooth control with the proprietary, free to download via App Store or Google Play Store, MW Connect app. Through the free MW Connect app, you can quickly toggle through all connected Fieldsheer powered by Mobile Warming technology garments and adjust individual heat levels to your liking. MW Connect app allows you to get real-time updates on battery levels and update your garments when new firmware becomes available. The Backcountry comes as a complete package with a 7.4-volt battery, charger, and stow bag. The Backcountry provides instant heat when the weather turns cold, keeping you outdoors and enjoying your favorite activity.