Want a discreet dashcam and a hands-free just as discreet? Here is the mirror of Interior NAV – 400.fhd! 
Features
- Dashboard camera and rearview mirror 3-in-1 "NAV – 400.fhd"
- Color screen built-in, diagonal image 4.5 "/ 11.4 cm
- Pixel video resolution: 1920 x 1080 (Full HD / 1080 p), 1280 x 720 (720 p), 848 x 480 (WVGA), 640 x 480 (VGA), format: AVI
- Photo resolution: 12, 10, 8, 5, 3, 2 or 1.3 Mpx, format: JPEG
- Field angle: 120 °
- Many recording options: accelerated mode, loop recording, HDR for HDR high dynamic range, timer, automatic recording by motion detection, surveillance parking function, timestamp
- Accelerometer: video evidence protected write in case of sudden braking or an accident, adjustable sensitivity
- Adjustable camera in all directions, about 30 °
- Bluetooth for hands-free feature, profile: HFP
- Microphone and speaker built-in function free hands and record / playback with sound
- Storage memory: up to 64 GB microSD(HC/XC) card (not supplied) slot
- Interfaces: Mini-USB (power supply), taken 2.5 mm jack for connection of a rear-view camera, output AV (3.5 mm jack)
- Food: Mini-USB vehicle power adapter (12 V and 24 V, cable length: approx.) 3.4 m), battery LiPo 200 mAh (in case of power failure)
- Size: easy attachment to the rear-view mirror by stretch bands
- Dimensions: 305 x 84 x 31 mm, weight: 249 g
- Provided NX4321 backup camera
The test
The NAV – 400.fhd is a mirror inside car that incorporates a front camera to use as dashcam, a screen to see what he records, in order to choose the options, etc… In addition to the front camera, it includes also a backup camera and a hands-free bluetooth! This is for me the 4 in 1 (mirror, dashcam, backup camera and handsfree), and it is rare! The fact that the mirror has a built-in camera and to act as dashcam already makes this very interesting mirror because it is virtually invisible! Be really careful to see that there is a camera, especially since usually the dashcams are ventousees or glued to the windshield, so hard seeing! So you have already less worry because he is less chance that a thief be tried by your dashcam because there are chances that he has just seen him! In case of problems / accidents also, it's handy to have a recording (except when it is you who are in the wrong ^^), but also in case of accidents, some like filming their journey. Furthermore, in case of shock, the camera automatically locks the file against deletion, thus avoiding any accidental erasure. The backup camera allows you to film what is happening at the back. There a hands-free built-in bluetooth makes it doubly interesting: no need for an additional new aircraft, or extra cable which is ride in the car! This mirror screen is not touch: on the one hand, this makes it more "tedious" setting (but theoretically, we do not daily), but on the other hand, no fingerprints on the mirror! Side setting, the 1st thing to say, is that the mirror is provided in… German… There is a user manual in french, but it is not precise enough so it took me a little time to figure out how to change the language. 
To change the language, press the button which is located to the right of the button 2 times ON / OFF, represented by a kind of drawer, menu. There you select "sprache" and then french, and there you will have much easier to set up, especially if like me you don't know little or no words in German! Then, quite a few options, the classic: definitions of the video, HDR, duration, time, plate, photos, frequency, etc… 
This mirror is also tinted blue to reduce glare! Be aware that the screen not gene not the vision back. And this screen can be turned off just by registering. In short: an excellent 3-in-1 mirror: mirror tinted blue to reduce glare, a dashcam with front and rear camera and a hands-free bluetooth! link: https://www.pearl.fr/article/NX4322/retroviseur-dashcam-fhd-avec-ecran-4-3-nav-400-hd-avec-camera-de-recul-bt 