Shure SLX 2 / Beta 87A / Q24 - handheld transmitter for SLX series with condenser capsule, super-cardioid polar pattern, display (group, channel and battery), frequency transmission from the receiver via infrared, 960 switchable frequencies, lock for menu and on/off switch, powered via 2x 1.5V batteries, frequency range Q24 736-754 MHz, up to 20 compatible systems (on multiple frequency bands, depending on national regulations).