Product Selection Guide WINDOW WALLS - PRODUCT COMPARISON YKK AP PRODUCT EFCO KAWNEER OLD CASTLE BUILDING ENVELOPE US ALUMINUM YCN 40 Offset Front-Loaded Ribbon Window Wall System - - - OS450 (4-1/2 " System) OS451 (4-3/4 " System) YCN 40 T Offset Front-Loaded Ribbon Window Wall System - - - - YSG 40 Structural Silicone Glazed Window Wall System S-901 - E-Z SETII BG 450 YSG 50 Structural Silicone Glazed Window Wall System YSG 50 - FG-3000 SSG BG 525 YSG 50 T Thermally Broken Structural Silicone Glazed Window Wall System S-902 - - BT 525 Thermal System 901 (NT) FG 623 ISOLOCK® (6 " System) Mor:Front FF 450 YWW 45 FI Front Set Window Wall System for Monolithic or Insulating Glass - FG 123 (6 " System) - FF 451 YWW 45 TU Thermally Broken Front Set Window Wall System for Insulating Glass - MetroView™ FG-501T PDR-225 (5 " depth) TT 451 YWW 45 FS Front Set Window Wall System Page-14 PS-1000-08 | Effective Date: April 28, 2020