Shure BLX24 PG58 Handheld Wireless Microphone System This package includes the BLX4 receiver and the BLX handheld transmitter with a PG58 mic capsule. The BLX transmitter features a popular mic capsule, a rugged and reliable ABS polymer chassis and frame, a 10 dB pad, an On/Off ergonomic push-button switch, and a single bi-color LED battery indicator. The BLX4 is a half-rack sized wireless receiver built into a rugged, polymer ABS chassis. It features advanced capabilities usually unavailable in wireless systems in this price range. The PG58 capsule is a popular mid-priced cardioid dynamic microphone capsule.