WHOOP 4.0 compatible. You’ve got goals and so do we—like keeping you charged wherever your day takes you. Get continuous data for days on a single charge with our waterproof* battery pack that enables you to charge on the go while you wear it. To charge your WHOOP® 4.0, simply slide the battery pack on your device to charge on the go. Use the included USB cable to recharge your battery pack from a laptop. *IP68 dust-proof and water-resistant up to 1 meter for 2 hours. WHOOP device and membership not included. Excellent working condition. Smoke-free home. Bundle & save!