MR- Moisture Resistant Plywood is not waterproof, but it can withstand moisture to a certain extent. When compared to BWR grade plywood, it is of lower quality. Urea Formaldehyde is the resin used to connect the sheets of wood in MR grade plywood. Indoor furniture such as chairs, beds, tables, and other objects are made using MR grade plywood. The only furniture that isn’t likely to get wet can be made with MR plywood.