Features include line-of-sight transmission up to 300', a built-in L-series battery plate on each unit, and durable metal housings. The transmitter and receiver each measure a petite 4 x 2.4" and are constructed with durable metal housings and a 1/4"-20 mounting thread. Both accept a wide 6-16 VDC input range and can be powered using an L-series type battery or the single included DC adapter. The Mars 300 set comes with five antennas (including one spare), a cold shoe, and a 1/4-20 adapter.The item "Hollyland Mars 300 Dual HDMI Wireless Video Transmitter & Receiver Set used once" is in sale since Wednesday, January 1, 2020. This item is in the category "Consumer Electronics\TV, Video & Home Audio\TV, Video & Audio Accessories\Audio/Video Transmitters". The seller is "antaig41" and is located in Chicago, Illinois. This item can be shipped to United States.