The Sennheiser IE 400 PRO dynamic, in-ear headphones for wireless monitoring systems offer musicians, DJs, and sound engineers a rich listening experience with clear, studio-like accuracy, when performing in quiet to moderately loud stage environments. With a secure, comfortable fit rivaling custom-molded models for isolation, the IE 400 PRO shields the user from excessive stage volumes and poor room acoustics to deliver punchy sound with transparent midrange.