主题：【求助】在美国的朋友怎么选床垫？ -- suney20

Any kind of wood board you find strong enough,

Plywood might be a good choice

http://www.homedepot.com/webapp/wcs/stores/servlet/ContentView?pn=Plywood&langId=-1&storeId=10051&catalogId=10053

You may not have the exact size to fit your bedframe--so maybe you need to buy several ones to put them together, but the store can saw the pieces for you if needed.