If you take video with mirrorless DSLR, do you need a monitor?

When we look at the components, we have a FEELWORLD FW703 monitor here. 

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Let your Video Shooting Become Easier 
● 7" IPS screen 3G-SDI 4K HDMI camera field monitor,Full HD 1920x1200 high resolution, High brightness: 450cd/m2,High Contrast: 1200:1, Aspect Ratio 16:10, Viewing angle: 80°/80°(L/R) 80°/80°(U/D), wide 160° viewing angle makes it easy for multiple members of the crew to watch it at the same time
● Inputs:3G-SDI, HDMI; outputs: 3G-SDI, HDMI, Stereo Headphone, Speaker (built-in), support 4K HDMI input and output
● Portable small size monitor, 320g lightweight, ultra-thin design 0.87 inch thickness, compact and rugged for stabilizer,it's easy to hold in your hands
● Professional Rec.709 HD color standard, and color calibration technology, with the professional instrument calibration at the factory, it can achieve monitor calibration efficiently and get accurate color reproduction easily, do not distort the color, show the real image when you shooting video
There is a mount that can be fixed and has a power supply.

 On the left side, there is a service USB terminal. This is the headphone jack, this is the current power jack. There is a built-in speaker. You can do hdmi input and output at the same time. I can output anything so I can connect with almost all other east. It is behind the speaker. It is behind the speaker. Now there is a menu button at the top. Doing things is a bit up and down. The operator is a bit hard to see how the button is pressed. If you search for batteries, you can purchase a number of batteries. If you use it outdoors, you will have to move the battery. I also bought two, I think I should use alternate charging. If it is used indoors only, you should be able to use it by connecting it to a power source.
It is the same.
More professional functions assist users to accurately monitor when shooting, making and playing movies/ videos：

Full HD 1920x1200
Richer, Brighter, Most Colorful
FEELWORLD FW703 4K monitor features "gold size" 7-inch full HD large screen, resolution 1920X1200, pixel density up to 323PPI. The outstanding image quality that allows you to achieve your "VISION".

IPS Wider View Angle 160°
Viewing Angle become very important, as the camera operators may shift his/her position relative to the monitor during the shot. FW703 IPS 160° wide viewing angle allows the operator to have a clear, easy-to-see image as their position shifts.

True Color · Professional Color Calibration
Use Rec.709 color standard
Accurate color reproduction

CLICK TO BUY: FEELWORLD FW703