Costco offers its members the PhoneSuit Elite Battery Case Bundle for Apple iPhone 4 / 4S in Black, model no. PS-ELITE-IP4-CSTBN3, for $69.99 with free shipping. (Non-members pay $4.25 more.) That's the lowest total price we could find for the PhoneSuit battery case alone by $10. Sales tax is added where applicable. The 2100 mAh PhoneSuit allows you to charge and sync your iPhone with iTunes with the case attached, and features an integrated power switch that provides access to the extra battery power when you decide. It also includes two sets of screen protectors and a USB car charger. Deal ends May 6.