'ANTIQUE' PLAIN BLOCK HO-SCALE RETAINING WINGS for recessed cut mountain portals. Sold in pairs. Measurements: 4-1/4" W x 4" H x 1/4" thick. ANTIQUE 'PLAIN BLOCK' SYSTEM is an integrated system of matching wall, portals & Scale Masonry Components: FL4161-HO single cut 'plain' block portal FL4191-HO 'plain' block retaining wingsset FL4271-HO double 'plain' block portal FL4181-HO 'plain' block twin culverts