IKEA Sultan Aram Slatted Mattress Base for sale. Good shape, only rarely used in the guest bedroom, non-smoking home with no pets. Wouldn't post for sale if it was disgusting or beat up.
Real wood slats provide a good base for the mattress and allow air to circulate.
The unique texture of the cover is the raw, non-colored and non-bleached linen, which produces subtle surface variations.
Simple to keep clean, because the cover can be removed and washed by hand.