Parrots must use the knob to turn the cover plate and expose the food items within each chamber. To release the wheel from the bracket, the caretaker will pull down the latch on the bottom of the bracket, raise the cover plate and unhook at the top. The wheel is then free unscrew the cover plate and fill the chambers, put the cover plate back on, hook the wheel on the top and fold down, secure to the bracket by pressing the bottom latch inward and it will snap closed. It only takes a moment but your parrot will be engaged for several hours.
To encourage a bird to keep working the wheel you should fill each chamber with a different food item. Suits larger food items, nuts, dried fruits etc, see image for e.g food items
Refillable, High interactive and Reinforcing, Stainless Steel Hardware, Constructed from Break Resistant Polycarbonate Plastic and Dishwasher Safe. The wheel securely screws on to cage from the outside.
My Eclectus and I love this toy. You can fill it differently each time to increase the challenge by covering the treats with paper etc. She always turns it to her favourite first. It can be a bit noisy when in use, but well worth it. The thread on the bracket of mine actually broke after very little use, however after contacting PRC they quickly offered to send a replacement part which arrived promptly. Easy to mount on the cage, and the quick release works great. I'm not sure how larger parrots would fare fitting their beak in through the hole, but our Ecky seems to manage well.