NEEWER CM4 3.5mm TRS Omnidirectional Microphone for DSLR Camera Recorder Model: CM28 Input: 5V 500mA Wireless Frequency Range: 2400~2483.5MHz Modulation Method: GFSK Audio Frequency Response: 30Hz~20KHz Wireless Transmitting Power: ≤10dBm Battery Type: 3.7V lithium battery Energy Saving Mode: Auto OFF after 5min Operating Temperature: 32–131°F/0–55°C Storage Temperature: -4–131°F/-20–55°C Dimensions (TX): 1.9"x1"x0.5"/47x26x13mm Dimensions (RX): 1.9"x1.1"x0.6"/47x29x14mm Weight (TX): 0.6oz/18g Weight (RX): 0.7oz/21g Charging Case Input: 5V 2A Battery Capacity: 2000mAh/3.7V Package Contents 1 x Charging Case 1 x Receiver 2 x Transmitter 2 x Windshield 1 x Camera Audio Cable 1 x USB Type C Cable 2 x OTG Adapter 1 x User Manual