Product Selection Guide CURTAIN WALLS - PRODUCT COMPARISON YKK AP PRODUCT YHC 300 OG impact resistant and blast mitigating outside glazed curtain wall system EFCO Series 5600 1600 Impact (2-1/2" Wide) 1630 SS IR (Screw Spline) OLD CASTLE BUILDING ENVELOPE US ALUMINUM HR-250 (Monolithic) HR-251 Series IW3250 (Insulating) HR-250 YHC 300 SSG impact resistant and blast mitigating structural silicone glazed curtain wall system - YHC 300 IG impact resistant and blast mitigating inside glazed curtain wall system - Page-26 KAWNEER 1600 Wall System™2 (Monolithic) HR-251 - (Insulating) - - - PS-1000-08 | Effective Date: April 28, 2020