A structure such as a table-tennis top or a table top may include a first portion and a second portion. The first portion may be constructed from blow-molded plastic and include a hollow interior portion that is formed during the blow-molding process. The first portion may also have a first set of characteristics such as lightweight. The second portion may be attached to the first portion and the second portion preferably has a second set of characteristics that are different than the first set of characteristics of the first portion. For example, the second portion may have increased mass relative to the first portion. The different characteristics may allow a structure such as a table-tennis top or table top to be constructed with desired characteristics.