The wood is standard black melamine particle board, probably picked up at Home Depot. My carpenter made it when the kitchen went in.
The shelf clips are pretty sturdy. I did add some double sided tape to the top of the clips to stop the shelf from sliding about.
The shelf supports that run up and down the cabinet are recessed into the wood. You'll need a dado blade on your table saw to cut the channel into the wood. They're screwed through the wood and into the studs on either side of the front of the cabinet.