SUN-MAR’s NEW Garden Composters incorporate our patented double drum Autoflow  design. With Autoflow, material goes in the top and compost exits out the end as the drum rotates.

As the drum rotates, compost moves along the outer drum and then back through  the inner drum before dropping from the output port

The 400 is considerably bigger than the 200, but otherwise it works on the same principle as the 200. The 400 is a continuous composter designed for composting kitchen scraps and a cut up materials from small garden.