With a slim profile, lighter design, and no Bluetooth, these battery packs are great for your fast and light, phone-free outings.

• 3 temperature settings adjust with the touch of a button
• Lightweight lithium-ion batteries last for up to 8 hours
• Battery packs attach snaps to the cuffs, where they are out of the way of boot tops
• Includes 2 batteries and a USB charger that can charge both batteries at once