ExpertPower Delta Mini- Ultra-Slim, Universal Portable Power Bank Charger for Apple/Android Phones & Tablets (Black) Delta Mini Black 4000mAh Ultra-Strong: Li-ion polymer cell and premium microchips are used to create our high-quality portable charger Ultra-Secure: Security protection designed for short-circuit and over-current protection. Ultra-Speed: A 2.1A output for faster charging of your ipad, camera, PC etc. and any other 1A output devices with over-current protection Ultra-Safe: Keeps charge with a standby time up to 6 months after fully charged. 500+ recharge cycles over the life of the battery