1, Outdoor Master EngineMain functions: video speaker phone, central monitor, unlocking by code, night patrol and card reading with multiple main engines and touch-free IC, providing entrance guarding by one pass card. 2, Power supply: DC18V/2000MA 3, Power consumption: ：250MA/900MA 4, Tone distortion: ≤ 8%SNR: ≥50db 5, Analytic degree: 420TV 6, LineLoad capacity: 800 doors 7, Camera lens: F1.8 78 degree or 92 degree 8, Minimum intensity of illumination: 9, Pattern: CCIRVideo output: 75/1V(p-p) Indoor Extension Main functions: speaker phone, monitor, unlocking, center and entrance guard calling, emergence alarm, 4 alarm connections for infrared, gate magnet, smoke and gas detections; Indoor ExtensionMain functions: speaker phone, lock opening, center and entrance guard calling, emergence alarm, 4 alarm connections for infrared, gate magnet, smoke and gas detections; Managing EngineMain functions: calls receiving, speaker phone, alarm, night patrol, card reading, unlocking, residents calling, stair entrance monitoring, data recording and computer connection.