HA100B - for flanged shelves 4-1/4" (ID) , plated to prevent rust  Sold individually HA120B – for straight sided shelves 4-1/4"(ID), plated to prevent rust  8.697-102.0 Sold individually HA130B 2-1/2" wand/utility hook for chemical shelves. Vinyl coated to avoid scratching and rust.  8.697-103.0 (use 2 to hang wand)  Sold individually

They are ¼" steel rod and shaped to assure a snug, no-rock fit to the shelf.