Rack receiver, Beta mic element.
The BLX24/B58 system contains the Shure BLX2 transmitter equipped with a Beta 58 capsule, and a BLX4 tabletop receiver.
The Beta 58 is a professional quality mic capsule with a neodymium element and a crisp, clear sound. It is the mic element of choice of many of the world's finest vocalists. With a hotter output than its predecessor, the SM58, and an improved response, it is seen on stages all over the world in some of the most demanding professional environments.
The BLX4R is a rackmountable, lightweight receiver with many features that are ordinarily found only on much more expensive models.