Good morning - it is made of polyethylene plastic
A little over a foot; about 18" maybe. It's a very generous size. You can take a normal household pail and dump contents into it no problem
Yes. FYI, the base has little wheels so you can easily roll the drum on top of it. But you can take the drum off the base and roll or carry it to another location. Base and Drum are independent (separate) pieces.
Hello, Maggie. This is what is included: (1) compost tumbling bin, (1) compost base wall section, (3) self-watering wall sections, (4) soaker hoses, (8) hose clamps and (4) wall stakes. The only thing in the picture not included are the plants and soil. Thank you for your question and have a great day.