In the past, getting ruggedized protection for your phone meant giving up cases with built-in battery extenders. Now, with the juice pack PRO from mophie, you can have both. The 2500mAh built-in battery, the largest ever included in a juice pack, can be used to constantly keep your iPhone 4 or 4S topped off at full power or held in reserve for emergency charging only. You can charge the juice pack PRO as you charge/sync your iPhone. The case has been designed to exceed the MIL-STD 810G standards for impact protection and dust/sand penetration set forth by the United States Military. While it’s not waterproof, the juice pack PRO offers protection from splashes and rain, dust and sand, impacts and drops, and vibration and shock. The mophie juice pack PRO is $129.95.