From inside (document excerpt):
Lift the bottom tab and lift the battery-case cover. Insert three AA drycells or NiCd battery cells here; close. and lock with the bottom tab. · FEATURES Telescopic Antenna I +- Rotate. stand up and extend fully when operating. · VHF FM MINI POWER TRANSCEIVER AL’NCO ExtemIII PO_ Tennlnall +-+ –. 00 not connect any power supply when dry ceUe are Installed in the radio. It NiCd baneries are inataned.