This Earphone

Buy.com has the JVC HA-NC80 Noise Cancelling Headphones for $31 with free shipping. 40mm driver, noise-canceling microphone reduces background noise and dual-plug adapter.
Able Planet Clear Harmony Stereo Headphone = $12 with free shipping.

Product description from Buy.com:

With the new JVC HANC80 noise canceling headphone, now y
ou can choose the most effective noise cancel mode for the circumstances. HANC80 offers both “wide” and “low” noise cancellation modes. The “wide” mode targets a wider frequency range than the “low” mode, and cancels the type of noise typically found in a commercial jet cabin. The “low” mode cancels a slightly narrower and lower frequency range, one associated with the noise generated by trains and buses. The HANC80 deliver up to 75% noise reduction, and also comes with fully padded closed earpieces which help to block ambient noise, and the padded soft touch headband ensure that they’ll remain comfortable throughout a long listening. It also offers a flat foldable style so that they’re easy to carry or pack, and comes with a carrying pouch and a dual-plug adapter.

FeaturesUp to 75% noise reduction (more than 12dB at 300Hz)Dual noise cancel mode - “wide” and “low” -Flat foldable designPowerful neodymium 30mm driver unitFrequency Response: 10 - 22,000 HzSensitivity:
103dB/1mW (when ON),105dB/1mW (when OFF)Weight: 5.82 ozCord !
Length:
4.9 ftGold plated plugPower supply: AAA battery x 1 (included)Battery Life: approximate 50 hoursAccessories: Carrying pouch,AAA battery x 1,Dual plug adapter

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