Measuring 4 inches tall by 3 15/16 inches at the widest point, this letter, T, is about 11/16 inch thick.  Made of unfinished California Redwood by Sierra Symbols, it is smooth on both sides.

 

The manufacturer recommends that an exterior type adhesive be used for any outdoor applications.  Other fasteners my be used, such as screws or nails, but any holes must be predrilled to avoid splitting the wood.  

New, this letter is in great condition.  Storage resulted in some fade marks where labels once were.  But these could easily be sanded or stained for more uniformity.