I've collected Westsail Head photos - very few ... in the members area.
Viewing the CHead model - looks like they use a second 3-5 gallon bucket as a holding tank with a special ventulation top to let the composting finish. A plus is that the bucket is easy to remove empty and replace.
Looking at the Nature's Head (and I assume the Air Head) you need to turn the whole unit upside down to empty the compost into a plastic bag or your compost pile.
Send in more images of your head to add to my collection.
Jay
Direct link