They're not the same. The motors for the slide in the 2104S are in the slide wall frame at the top on each side. There is no manual crank on this system (the link Dave provided will explain it). The motor controller is located on the front wall of the trailer in the pass through storage just to the left of the water filter. If, for instance, one motor burns up you can put it in override and have someone help push will you operate the other motor. If something were to short out, you would disconnect the motors from the controller and you would be able to just push the slide in and reconnect it to lock it. If a motor froze up, you can access the motors from the outside and remove a set screw to lift the motors out of the way and the slide will move freely.
Also, the jack can be cranked down with one of the cranks that came with the trailer. You access the nut on the jack through the hole the bubble level on top is covering.
2015 Chevy Silverado LTZ - HD tow package
2017 Rockwood 2703WS Emerald Edition