Mackie MP-220 is a in-ear headphones designed to provide better sound isolation and full-range frequency reproduction for musicians, vocalists and sound engineers during recording sessions in the studio and live. The high-performance, double, dynamic drivers in each headphone provide a frequency response from 20 Hz to 20 kHz, with emphasis on clear bass and detail. The headphones have a low profile construction with molded casings for ergonomic fit and up to 40 dB noise isolation. MMCX connectors allow you to unplug the braided shield for easy storage or replacement. Accessories supplied with the MP-220 are foam, silicone and dual-head inserts in various sizes, gold-plated adapter 3.5 mm to 1/4 "and a molded hard case Sensitivity: 104 dB, converter: double hybrid, impedance: 8 ohms; frequency range : 20 - 20,000 Hz, dual dynamic driver, ergonomically shaped low profile housing, high quality cable with detachable MMCX connector, color: black; contains a hard case, gold-plated 3.5 mm sockets for 6.3 mm adapters, foam earbuds, silicone and double collar in 3 sizes.