Had these fall off my 2012 Flagstaff 831fkbs. The slide actually scored or dug into the vinyl flooring. Takesd to FR and they advised to replace the item before more damage occurred. Pieces are held in by a couple of screws and are easy to replace, when the slide is extended. Ours fell out, so I added a couple of strips of to the floor where the slide came in. Solved the scoring issue and slide seemed to retract easier.
Marriot2 on Wheels 2017 Flagstaff Classic 832 OKBS
2013 GMC Denali 6.6L 2500 HD DMAX w\Alison Trans
Pepper Pomeranian rescue 121 days as camping buddy
Days camped in FR, 2011 = 20, 2012 = 57, 2013 = 59
... 2014 = 39, 2015 = 52, 2016 = 77, 2017 = 11