Retaining Wall Systems Kingston Block and Masonry Supply is the exclusive area licensed manufacturer of Omega and Alpha segmental retaining wall systems. Products Omega Wall Alpha Wall Colors Products Select a Product to View ARCHITECTURAL BLOCK ---- Ground Face ---- Jewel Stone ---- Cemento Brick ---- Split Face ---- Sound Cell ---- Custom Block ---- Colors RETAINING WALL SYSTEMS ---- Omega Wall ---- Alpha Wall GREEN PRODUCTS "LEED" ---- Jewel Stone ---- Pozzotive™ CMU Block RECENT PROJECTS