I have recently seen two eBay auctions of Phototherm units with 4x5 inserts that were made out of Patterson reels.
One currently listed is here: http://www.ebay.com/itm/PHOTO-THERM-...99344643062561
Look at the eighth picture.
The one which recently closed, and I did not win, was for a broken unit. Here: http://cgi.ebay.com/ws/eBayISAPI.dll...vip=true&rt=nc
Look at the third picture, the unit on the left.
Has anyone ever seen one of these 4x5 inserts? Got any pictures? Can you make one at home out of things laying around?