Mail Boss Townhouse Wall Mount Locking Mail Box Granite - Mail Boss 7171 by Mail Boss. $129.00. Stainless steel hinges for lasting use. Locking access door. 14- and 16-gauge welded electro-galvanized steel. Commercial grade 7-pin brass core tube lock. Innovative patented anti-pry latch locking mechanism to prevent leveraged entry. Mail Boss 7171 Townhouse Wall Mount Locking Mail Box Granite.