Works on Single or Double Doors For 10 or 12 mm Glass Field Reversible 304 Grade Stainless Steel – Available in Brushed or Polished The CRL latch comes assembled for use with the EC4 Keyed Cylinder on all outswing and on inswing doors without a Glass Mounted Latch Keeper. NOTE: When used on door-to-door applications, the door with the keeper should be secured in place with a lock at the bottom of the door. GLASS FABRICATION REQUIRED:Two 45mm Holes COMES WITH:ES3 and ES4 Series Cylinder/Thumbturn with 3 keys each, Template and Instructions.