Overview Reviews Product Description Closed-back design for maximum sound quality Frequency response of 15-25,000 Hz Lightweight design and adjustable headband for a secure fit Soft foam ear cups for added comfort Product Videos Custom Field Product Reviews Write a Review Write a Review × KOSS Koss Portapro-KTC Portable On-Ear Wired Headphones Rating * Select Rating 1 star (worst) 2 stars 3 stars (average) 4 stars 5 stars (best) Name Email * Review Subject * Comments *