J&R via Amazon offers the Sennheiser CX 275 S In-Ear Stereo Headset, model no. 504538, for $24.95 with free shipping. That's the lowest total price we could find by $12, although most merchants charge $50 or more. This in-ear headset features a 17Hz to 23kHz frequency response, music and volume controls, a microphone, different sized eartips, and storage pouch.