But before you go shopping, measure your mattress carefully - length, width, and depth. Many RV mattresses are made to fit into the available space and are non-standard sizes. This affects not only what mattress you can replace it with, but also the linens that will fit it. Newer ones often are thicker. Or maybe thicker won't work if there's storage under the bed and you have to lift the bed to put things under it. The board on which our mattress sits lifts up and almost touches the ceiling. Thinner would fit but thicker might not.
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