Steel Windows Selection GuideKey: Most Popular Applications Commonly Used Applications(click dot to go to product)Download PDF VersionExisting Window TypeExterior UseInterior UseNotesHOLHOL-OPHOL-TORAOLMAOLMOLMOL- STMOL- OPMMOLSAWSteel WindowsDouble Hung (Both Sash Operate) Single Hung (Top Sash Fixed) Casement (Single-Swing Out) Casement (Single-Swing In) Double Casement (Both-Swing Out) Projected (Push-Out) Hopper (Tilt-In) Hopper vent must clear stopsHorizontal Pivot (Swings in and out) Fixed Vertical Folding (Pushes-out) Curtainwall Special Steel Window ConsiderationsSpecial Shapes Bowed Screens Protective Glazing Between-Glass Blinds Very Large Units Various models can be mulled