This is a set of 1/2" MDF YZ plates.
1/16" holes for #4 wood screws on the linear rails.
Wood stain works well to make these any color you want. Paste wax can seal them up for getting dirty if you like the raw look.
New LR3 Parts, I will be making these to order so they typically will take a few days to a couple of weeks to ship until things stabilize, and the future price could be different from what you pay. If it goes down within one week of your order I will refund you I will not charge you if it goes up. If you are uncomfortable with that, please wait a week or two for me to figure this new build out.