Mobix for Apple Iphone 5 5s 5c 4200mah External Rechargeable Spare Backup Extended Battery Charger Pack Case Cover-Compatible with iPhone 5 5s 5c (Gold) Unique design for acoustic sound enhancement. Combines rechargeable back up battery with ultimate protection. 2 pc slide on detachable hard PC back cover shell case with rubberized coating finish on both exterior and interior. Extra shock absorbing, skid-proof, tear-resistant, anti-scratch, and anti-fingerprints protection. Standby/Charging switch at the bottom frame allows easy switching between standby and charging mode.