Staples offers the Sennheiser PX 685i adidas Sports Headphones for $34.99. Plus, Staples Rewards members receive free shipping. (Not a member? It's free to sign up.) That's tied with last week's mention and the lowest total price we could find by $2. The headphones feature sweat and water resistance, 18Hz to 20kHz frequency response, and an in-line remote and microphone. Deal ends October 28.