This rock-surface battery pack is just what you need to stay charged no matter what the day brings.

The SHARKK packs tons of power and includes optimized outputs for charging both tablets and phones, and thanks to Cult of Android deals, it’s half price for a limited time.

With convenient dual-ports for simultaneous charging, the SHARKK is guaranteed to be your rock through thick and thin. It has a sleek and compact design that easily slips into a purse, backpack, or even your pocket, and a whopping 15,000mAh battery capacity; that’s up to 6 full iPhone charges, or 4 full charges of the Galaxy S6.

LED indicators help you see how much battery life is left at a glance, and dual-USB ports let you charge two devices simultaneously. And because the SHARKK uses standard USB ports, you can charge anything from smartphones and tablets to cameras and handheld consoles.

The SHARKK is normally priced at $60, but thanks to Cult of Android Deals, you can get yours for just $29.99 — with free shipping across the U.S. — for a limited time.