D & M
stands for Design and Manufactering- They built darn near everybodys dishwashers through the 50-70s.They built dishwashers for Sears Kenmore,Magic Chef, Tappan, Preway, Caloric, Speed Queen, Modern Maid,I think some Kelvys, Roper and anyone else that wanted to have a "me too" dishwasher in their appliance line up. These are the folks that brought up the much-loved Roto-Rack-the round upper rack that spun around past the sprayer