They only make a downdraft range combo with the vent in the center. Jenn Air and Kitchen Aid make this option. If you 100% want it in the rear, then you can buy any slide in, and as long as you have the extra depth, brands like Elica Best and Zephyr make downdrafts specially designed to go behind a range. The issue is the motor will have to go behind it or in a basement remotely mounted, so the setup is more complicated to achieve and usually needs a much deeper cutout.