Looking for info on a mattress

[Dennis F]

We're picking up a 355RK Avalanche with a king size bed. We want to go get a set of sheets for it tonight but was wondering if the thickness is like a regular size mattress or if it is a deep mattress. If someone out there has this model trailer could you please let me know. TIA

[Road Ranger]

We wondered about that, too, when we got our 5th wheel so we just used a tape measure to get the thickness of the mattress and went with that to the linen store. But first, we switched from a king to a queen size mattress and cut and sanded the mattress board to fit (the board under the mattress). For us, we were too far apart in the king size and making this change gave us more room around the sides of the bed for getting the bed made as well as for just getting in and out. 'Worked for us, anyway.