DEITY V-Mic D4 DUO This is a unique on-camera microphone that can record sound from both front and rear. It's perfect for outings, vlogs, and other uses. Only the image is included. Those unfamiliar with it can download the instruction manual from the website. You can also change the input from the rear microphone to an external input, allowing you to configure 2 channels with a lavalier microphone + a shotgun microphone. 【Dual Cardioid Pickup Design】: The bi-directional sound pickup design allows you to record audio not only from the front of the camera but also from behind the camera. 【Compact Design】: The D4 DUO is a compact external microphone, perfect for use with small mirrorless cameras and DSLR cameras. It weighs only 40g / 1.4oz. Dimensions: 21mmD x 93.5mmH 【AUX 3.5mm Input】: The 3.5mm AUX input bypasses the audio from the rear capsule and sends it to the right channel of the camera, allowing you to add other small microphones or wireless receivers. Simply switch to stereo and connect a lavalier or wireless receiver. 【Dual Mono/Stereo】: The switch on the upper right allows you to freely switch between bi-directional and unidirectional sound pickup modes. You can select the sound pickup mode depending on the situation using the switch, making it great for recording radio programs, interviews, and posting YouTube videos! 【No Battery Required】: No external power is needed; it can be connected to a DSLR/video camera/smartphone via a TRS 3.5mm cable. Frequency: 50Hz-20KHz Polar Pattern: Cardioid Capsule Type: Back Electret Condenser Sensitivity: Front (-42±3dB re 1 V / Pa @ 1kHz) / Rear (-51±3dB re 1 V / Pa @ 1kHz) SPL: 120dB (@ 1KHz, 1% THD at 1K) Operating Voltage: External Bias Voltage AUX Input Connector: TRS 3.5mm AUX Input Voltage: 2-5VDC Output Connector: TRS 3.5mm Output Type: Dual Mono/Stereo Material: Aluminum Capsule Size: 21cmD x 93.5cmH Weight: 40g