ClosetMaid has a lot of options that fit onto their Wire Shelving. They have a variety of drawers available, but this one seems to be the best value.
They are available in two finishes, white or nickel. White is usually less expensive.
The sizes are quite practical. The single drawer is 4″ deep. The double is 7″ deep.
The triple, not part of this kit, is 11″ deep.
All of the drawers are 17″ wide by 21″ front to back.
The brackets that hold the drawer fit into the upright wall brackets, call Hang Standards. They just hook in, just like shelves.
You can add them to any of the closet kits.
ClosetMaid 4-Drawer Kit Installation Instructions
To support drawer system, place two Hang Standards (not included) 20.5″ apart (center-to-center).
Identify bracket (“R”) and bracket (“L”).
Insert brackets into corresponding “inside” slots on Hang Standards.
A. Hook Shelf into front groove of each bracket.
B. Place back wires into back holes on bracket.
C. Snap clips in place.
Secure hang standards to wall. Slide supplied drawer into lower channels on each bracket.
Repeat steps 2, 3 and 4 for remaining drawer(s) working from the bottom to the top.
Allow 7 spaces between brackets for 7″ High Drawers and 4 spaces for 4″ high drawers.