This is from the Trekwood site,
https://www.trekwood.com/parts-searc...ry=Seal&page=1, shows all the possible seals for your rig.
On our rig, there are two seals for the slides that are on all our hydraulic slides,
https://www.trekwood.com/products/44...lip-On-1225-Bx
and
https://www.trekwood.com/products/44...k-Wall-1000-Bx
Both seals are fairly easy to replace, but you have to remove screws at various places to get the seals off, and then you reinstall the screws. You do not need to purchase from Trekwood, but the part numbers help identify which seals to search for on Amazon or other sites.