The Fieldsheer powered by Mobile Warming heating technology Backcountry Heated Jacket made with Primaloft synthetic down comes in 2 colors and offers a low-profile 7.4-volt battery. With Waterpell technology, water bounces off the garment. 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 Jacket.