World Wide Stereo via eBay offers the Sennheiser MM 550 Travel Bluetooth Wireless Stereo Headset, model no. 502417, for $249.99 with free shipping. That's $20 under our expired mention from three days ago and the lowest total price we've seen for these headphones. (They're a current price low by $250.) These over-ear headphones claim to reduce up to 90% of all outside noise via active noise cancellation. They have a 1-touch microphone and fold-away design. Deal ends March 5 at 3:22 pm ET.