Openuye via Amazon offers the Openuye 5,000mAh 5.5" Battery Case for iPhone in Gray for $29.99. Coupon code "UU569773" drops the price to $20.99. With free shipping, that's tied with our mention from three weeks ago, $9 off, and the lowest price we could find. The silicone case is compatible with iPhone 8 Plus / 7 Plus / 6S Plus / 6 Plus and features 360° full edge protection and up to 200% extra standard battery life.