A contemporary classic, our Ultimate Double Hung Next Generation window blends traditional beauty with state-of-the-art window performance.Features DESIGN VERSATILITY: With an array of simulated divided lite patterns, interior and exterior color options, ten hardware finishes, and hundreds of roundtop sizes. EXCLUSIVE AUTOLOCK: Activates when the sashes are closed, locking the window. ALUMINUM INTER-LOCK: Eliminates drafts and improves the window’s overall structural integrity. NARROW CHECKRAIL: Provides a sleek aesthetic to maximize daylight opening while maintaining historical accuracy. SASH BALANCE SYSTEMS: Enable smooth operation even at the largest sizes. FIRST-RATE ENERGY EFFICIENCY: Meet ENERGY STAR standards in energy efficiency with multiple glass options for various regions, climates and weather needs. EXPANSIVE SIZES: Up to 5’ wide by 10’ tall.