This 50 pack of durable and sleek Smart-Trek™ deluxe headsets are versatile and compatible with a wide variety of technologies. Designed to stand up to the K-12 environment, Smart-Trek™ headsets are built to last. The Smart-Trek™ series features a rugged and comfortable design, so teachers can have headsets that will function for years, and students can wear the headsets for an extended period of time. Smart-Trek™ headsets feature an easily adjustable headband to fit students of all ages; ear cups made with high-quality leatherette ear cushions that are easy to clean, durable, and provide excellent noise-isolation for better concentration; a durable, flexible, steel-reinforced gooseneck microphone; and Dura-Cord™ – the chew, kink and knot-resistant, PVC-jacketed, braided nylon cord. Best of all Smart-Trek™ headsets are compatible with Chromebooks, PCs, Macs with 3.5 mm headphone port, iPods, iTouches, MP3 players, CD players, stereos and most gaming systems." Drivers: 40 mm Impedance: 32Ω Frequency Response: 50Hz - 20KHz Sensitivity: 100dB±4dB Warranty: 1 Year 5' Dura-Cord™ - chew-resistant, PVC-jacketed, braided nylon 120° 3.5mm TRS plug