Tiergrade via Amazon offers Prime members its Tiergrade Wireless Magnet Attraction In-Ear Bluetooth Headphones for $29.99. Coupon code "8BLD3MVN" drops it to $19.99. Plus, Prime members bag free shipping. (Non-members can spend $49 or more to qualify for free shipping; otherwise, shipping costs $6.) That's $20 off list and the lowest total price we could find, although we saw them for a buck less in November. They feature HD voice technology, up to five hours of use on a single charge, and are compatible with iOS or Android devices.