The ClosetMaid® White Wall Clip Set is designed to support ventilated wire shelving and can be installed in both drywall and concrete/studs. When installing fixed-mounted shelving, use 1-shelf clip every 12 in. and one at each end of the shelf to securely hold the ventilated wire shelving (sold separately). Metal screws and plastic anchors are included for installing the clips, which are constructed of white PVC for durability.