Mine are not "real". For the thread I cut the ends off a 3" riser, took photos and then edited them in Photoshop to color in the openings. Plarnolds look to be a manufactured accessory. If I knew how to form and mold plastic I would have created many of those for our layout although I would have made ours in the light gray. They would be perfect to clean up the tops and also they would lock down the tracks with that lip.
![[Image: 7071.gif]](https://www.allsmileys.com/files/sweetim-texticons/7071.gif)