116 =
116 is just the prefix of the model number, this designates the manufacturer, 116 = Birtman electric co before 1957, Whirlpool cooperation after 57, yours is probably late 40s or early 50s...Wonderful machines, you can tell a Birtman machine by the sound, they also made their own machine called Bee Vac and they built a machine for L.C. Mayer company, called the Lyceum.Birtman was taken over by Whirlpool, the reason for this was Sears wanted to get more manufacturing under 1 management, so they got Whirlpool , who already made their laundry equipment, to buy out Seeger Refrigeration Co, who made the Coldspot refrigerators, and Birtman, who made vacuums, mixers and blenders, somehow in the deal, the mixer/blender stuff got farmed out to Hamilton Beach, the hamilton Beach built stuff will have a 400 prefix.For a while, HB continued making mixers almost identical to the Birtman built ones, the only difference in the Whirlpool vacuums, is Whirlpool did not make their own motors, Birtman did, and all you have to do is listen to one and you can pick that startup sound out of a group of vacuums, its that distinctive.