The MIPRO ACT-3H (6B) Supercardioid Condenser Handheld Microphone with frequency 6B provides a precise and rapid frequency sync to the transmitters with ACT function. The ACT-3H (6A) features built-in anti-pop filters and anti-roll ring, and an interchangeable module for replacement and servicing. It also offers high SPL inputs without distortion and CPU-controlled oscillation technology. The MIPRO ACT-3H (6B) has a housing that includes a power & low battery LED indicator, up to 24-hour battery life with dual AA-sized batteries.