You're thinking of the old model, Monty: "Unlike monty, QA is 100% battery powered, and gets 4-6 hours of runtime on every charge. Monty's pneumatics required

You're thinking of the old model, Monty: "Unlike monty, QA is 100% battery powered, and gets 4-6 hours of runtime on every charge. Monty's pneumatics required it to be tethered at all times. Also, its much lighter at around 35lbs. Monty is too heavy to pick up."