Singers, musicians, and music lovers will love the Westone MACH 20, a pair of dual-driver universal-fit in-ear monitors that feature a balanced clear top end and a big and punchy low-end response, well suited for onstage monitoring, vocalists, guitar players, keyboard players, drummers, and sound engineers. The earphones employ Westone's proprietary dual-driver system with a single balanced-armature driver for bass frequencies and a single balanced-armature mid-high driver, which combine to deliver a frequency response of 20 Hz to 18 kHz at a sensitivity of 110 dB SPL. The MACH 20 utilizes a Linum Estron BaX cable that consists of thin and ultrastrong silver-plated copper. The BaX conveys music with precision and grace, while the lightweight cable disappears on your ear, allowing you to focus on what matters most. Included with these earphones are five pairs of silicone eartips of various sizes, five pairs of foam eartips (also in various sizes), an audio cloth bag, and a monitor vault.