These are New old stock used for older cabinet Drawers. They have been in a shop for a while so they are dusty/ a little rusty on some. These are what the drawer rollers ride on and back end is adjustable to wherever you need it. You can slide the one piece on the length to accommodate your situation. They come in a set of 2 for left and right. If you need the drawer mounted rollers you can view those here: https://ebay.us/m/xzODYm
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