Koss Headphones - Ever since Koss invented the world's first SP/3 Stereophone back in 1958, Koss Stereophones have been bringing back the excitement of a live performance. Music lovers around the world recognize that dedication to accuracy in sound reproduction as: The Sound of Koss®. Koss offers International Shipping from the USA to most countries and regions. In 2024, Koss celebrated the 40th anniversary of this legendary headphone with the launch of the next-generation Porta Pro Wireless, highlighted by a double-sided, retro-themed billboard near the company's world headquarters in Milwaukee, WI. This special installation paid homage to the original design and legacy of the Porta Pro, while introducing a modern evolution of its beloved sound and style.