'HOWARD STREET' HO-SCALE SINGLE STONE BLOCK PORTAL - Part of the "Howard Street" Masonry System modelled after the Pennsy style architecture. Overall outside dimension 6-3/4" w x 4-3/4" h x 3/4" thick. HOWARD STREET MASONRY SYSTEM is an integrated system of matching wall, portals & Scale Masonry Components: Components: FL4158 - "Howard St." Seam Sealers; FL4159 - HO Single Stone Block Portal; FL4260 - HO Double Stone Blck Portal; and FL4190 - HO Stone Blck Retaing Wings.