Combining a pair of HOTRONIC XLP 1P BT Battery Packs with the Soft Compression and Surround Heating Element of the Surround Comfort sock the Hotronic Heat Socks Set XLP 1P BT Surround Comfort kit is everything you need to keep your toes warm packed neatly in a box. The same comfortable cushioned compression socks, and the same control via the Bluetooth Ap as the 2P powered sock, the difference between the two is these have a 2000mAh capacity for 10 hours of heat vs. the higher capacity battery. The socks’ Surround Heating Element envelopes your tender toes with constant heat. The best size to capacity ratio on the market these batteries ride tucked into the cuff with power wires positioned along the lower leg and wrapping ergonomically around the Achilles and under the arch to deliver heat to the top and bottom of your toes. If you’re looking for a warmth solution in a flexibly fit sock designed for normal capacity boots and shoes, from your hikers to your ski boots but don’t need the extended power range of the 2P battery, these are your new best cold weather friends.