Sennheiser HD 239 On-Ear Headphones for $40 + free shipping
Newegg offers the Sennheiser HD 239 On-Ear Headphones for $59.95. Coupon code "618CMPTS78" cuts it to $39.95. With free shipping, that's $30 under the lowest total price we could find, although we saw them bundled with a bluetooth speaker for a few pennies cheaper last winter. These open-back headphones feature a frequency response range of 16 to 23kHz, a foldable design, and a storage pouch.
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