As one of its daily deals, All4Cellular offers the refurbished SaFPWR Milano Rechargeable Smart Battery Case for iPhone 4 and 4S in four colors (Shiraz Red Crocodile pictured) for $14.99 with free shipping. That's $30 under our November mention of a new unit and the lowest total price we could now find for a refurb by $5. (For further comparison, it's also $14 under the best price we could now find for a new one.) This case purports to double the battery life for an iPhone 4 or 4S. Deal ends today.