Sennheiser MX300 In-Ear Headphone with Bass Driven Design (Discontinued by Manufacturer) Lightweight in-ear headphones for connecting to portable audio devices Bass-driven design optimized for rock and pop music 18 Hz to 20 kHz frequency response; ear pads offer added protection 3.5 mm mini-stereo plug plus 1/4-inch adapter Weighs 0.21 ounces (without cable); 2-year warranty