Today's tech-connected kids live in a high-def world. They experience Blu-ray, surround-sound, life-like computer graphics and 3-D movies. They are bombarded by sound from television, toys, game consoles, music players and in-vehicle entertainment systems. ETYKids safe-listening earphones are engineered for safe sound output while maintaining Etymotic's exceptional sound quality. By controlling earphone sensitivity, it is not necessary to restrict the volume setting on the player. Sound heard through ETYKids earphones will not exceed safe levels, so parents can rest easy. Even at the maximum volume setting on portable players, kids can listen safely for up to four hours per day. And because ETYKids earphones block background noise, and provide high-definition sound quality, kids will be able to hear every detail, and won't complain that the volume is too low. Frequency response: 20 Hz - 15 kHz. Impedance: 300 Ohm. Included case and a assortment of ACCU fit ear tips.