Here’s something to keep your mobile device running much, much longer. Like a week. Seriously. The aptly-named Dark Energy Reservoir is a USB charger with an 8,000 MAH capacity that can increase the longevity of your iPhone, tablet, or other device four times over. With two USB ports, you’re free to take advantage of its rapid charging capabilities using two devices. The best part? It’s super lightweight and sleekly-designed, meaning the doubletakes its gets from your colleagues may be the only thing to remind you that you’re carrying it in the first place. Never suffer from #FOMO again.