CX 3.00 Spice up your sound with Sennheiser’s new CX 3.00 earphones which offer amazingly detailed sound reproduction and enhanced bass response in an incredibly small package. The in-ear design reduces ambient noise to a minimum, and the included set of ear adapters guarantees an individualized fit with four sizes (XS, S, M, L) to choose from. These are the earphones you’ve been looking for.