Koss Porta Pro Headphones [$49.99] are the most popular headphones on koss.com. Koss has been a leader in the headphone game since 1984. Since then, to the delight of Porta Pro enthusiasts, Koss continues to remain loyal the original design and performance that made the Porta Pro the benchmark of portable music. Constructed with Mylar, the components of the frame are nice and rigid, which is crucial in producing exceedingly accurate sound reproduction. Koss Porta Pros Headphones deliver astonishing rich, deep bass, balanced with an enveloping wide frequency response.