My coach has double pane windows with the name Penwin etched into a corner. They are made (still) by Motion Glass (http://www.motionwindows.com/index.php). Mine are series 1800. Just an FYI!
1993 32' Regency Wide Body, 4 speed Allison Trans, Front Entry door, Diamond Plate aluminum roof & 1981 Euro 22' w Chevy 350 engine and TH 400 tranny