I'm planning to build built-in cabinets in my office.Ideally I want an adjustable shelf or two. I'm trying to find a relatively hidden way of having adjustable shelves as opposed to having those big metal rails. I found this photo which is almost identical to what I want
http://www.rrsva.com/DSC00113.JPG . I can see holes up the left side where the shelves can be moved to. Are there some brackets that are pushed into those holes, then have a flat area to hold the shelf? I'm thinking that must be what it uses, but I can't find them by searching but maybe I just don't have the right terms. i simply searched things like 'adjustable shelf bracket', etc. Any guidance would be appreciated.
Thanks!