Flexible & fun. Hearing is believing. The Sound of Koss: 3.5 mm; 4 foot; 40-20k Hz; 32 ohms; 100 dB SPL. 1-800-USA-Koss (1-800-872-5677). For warranty information visit www.koss.com. Limited lifetime warranty. Comfortable fit. Bold colors. Bright & stylish. Limited lifetime warranty. Smart phone compatible. Super soft. Flexible fit. CE listed. Printed in China. Made in China.