According to market research, 4.3-inch is the most suitable size for small and medium-sized cars, it can fully show the road condition. and the monitor can be placed on the windshield and dashboard, no worry that the driver will be disturbed by the large monitor when driving, and avoid the crowed car environment.
https://www.amazon.com/Digital-Wireless-CS-2-Monitor-Reversing/dp/B07GVC156F

