Cobra runs single car trains, like a wild mouse. They took all but 2 cars off the track for us. We couldn't use a small lipstick camera as we can't connect those to our radio link back to the satellite truck and they're not totally broadcast quality. So we had to use a relatively large Sony Z1. We needed the shot to be as steady as possible so used 2 magic arms to mount the camera to the lapbar plus a 3rd to stop the camera rotating and then ratchet straps going off in 3 other directions for additional bracing. Some of the additional mounting kit you can see is for the radio transmitter.
OH and the BBC requires everything to have safety lines so the camera, lens, radio transmitter, magic arms all required lanyards in case they came loose. So yet more complicated mounting gear.