... Video Audio CCTV Tester. Video Test, audio test. Lithium battery build-in. Speaker build-in ----test box Item ... --- It built in speaker, can test the audio. Rechargeable Lithium Ion Polymer Batteries more reliable, and work 5 hours Specification ... pAudio Input8 Ohm 1WOSD menuEnglishPower inDC12VBatteryLithium rechargeable battery 3.7V 1100mAhRechargeable5 hours rechargeable time, work for 5 hoursLow ...