Amazon offers its Prime members the Supcase Unicorn Beetle Pro Rugged Holster Case with Screen Protector for iPhone 6 & 6S in Black/Black for $14.49 with free shipping. (Non-members can spend $49 or more to qualify for free shipping; otherwise, shipping costs $6.22.) That's the lowest total price we could find by $2. This shock-resistant case features a dual-layer polycarbonate shell, screen protector, and belt clip.

Update: Specs corrected.