Staples offers the Sony ZX Series Noise-Canceling Headphones in Black, model no. MDR-ZX110NC, for $24.99. Plus, Staples Rewards members receive free shipping. (Not a member? It's free to join.) That's $9 under last week's mention and the lowest total price we could find by $20. They feature a frequency response of 12Hz to 22kHz, 10 dB/mW sensitivity, and 45 Ohm impedence.