2 video input from 2 cameras in 1 output device

the device im looking for must have 2 channels for 2 cameras and i watch the video of them in same time in screen split. the half sceen play the first camera and on the other half screen play the second camera. without remotes or more than 2 channels. the voltage of device must be 12v or less, never mind and when i push a switch or button (and this parameter never mind) start whole the project.

Project ID: 19445679