Sennheiser Rf System Package For Single Channel Applications. Includes (1) Sr2020-D-Us Rack-Mountable Transmitter, (1) Am2 Front-Mount Antenna Mounting Kit, (5) Hde2020-D-Ii Us Receivers, (1) Ezl 2020L Charger Case And (1) Ada Signage Kit, Sr2020-D-u