This particular wire is commonly used in the stucco system and is a fairly strong kind of wire. It is furred, which means that it sticks off of the wall a little bit (about a quarter inch or so) so that the stucco mix can "key" in behind it. You really want the wire to be in the middle of your base coat, for the best possible installation. The wire can come in a non-furred version but is hardly used because you would have to use furred nails instead and most codes require the use of furred wire anyways. The wire is typically galvanized, in order to prevent corrosion of the wire over the years. The holes in the wire are approximately 1 1/2 inches apart (depending on manufacturer), which doesn't really matter but is just another identifying factor for stucco wire.