That's the type of storage unit which I used in our Boler
B1700 closet; in Canada, this particular brand is found under the "Gracious Living" brand name (and probably others) at major chains such as Home Depot and Canadian Tire. While there are some minor variations, they all seem to be modular: each drawer is in a section of the cabinet which snaps together with the other sections and a top plate to finish it off.
The modular construction means that you can assemble whatever combination of shallow and deep drawers meets your needs and best fits the closet - ours is as tall as can fit in the closet, and is mostly deep drawers. Due to the curve of the trailer wall, there is still a space on top for more stuff.
I just placed mine on the closet floor, which is quite high in our Boler
, so there are no shelves involved. The shelves in Jackie's setup allow for a mix of drawers and full-width open storage, which is a nice feature.