Features:Ideal add-on to your CCTV DVR System. Simply plug into your DVR Audio Channel using a Phono Cable. It requires a 12V power supplyIt��s used both Indoor and Outdoor (Outdoor with suitable protection from the rain)2 Connectors: One is a phono connector for audio while the other one is a DC power connectorCan be fitted on ceilings， walls， in suspended ceilings， under roofs， under soffits， cashier/ till desk at your business， behind a sofa inside a living room， etcConnects directly to you DVR， no need for an amplifierPower Supply Required: 12V DC (Not included)Current Consumption: 200mAAudio Range: up to 20-30 metres (omni-directional)Frequency Range: 10-2000kHzPackage Included:1 x Security CCTV Audio Microphone Sensitive Mic