One of the standard models of the Shay built in larger numbers was the class B in the version with a service weight of about 50 short tons. Like all B, C and D class models, they had three cylinders. Some of the B-50-2 model locomotives already had a boiler pressure of 220 psi, while most others were still operated at 200 psi. In the meantime, the gear parts on the right side of the locomotives were covered to protect them from dirt while working in the forest. Curb weight was 85,800 pounds for early examples and approached 99,000 pounds for locomotives from the mid-20's.

The Lake Independence Lumber Company in Michigan operated a total of five B-50-2s in addition to one B-42-2. Two of these had been built in 1910 and 1911 for other logging companies and came to this company later. Two more had been built directly for the Lake Independence Lumber Co. in 1914 and 1925 and an identical 1923 example had been purchased from Lima stocks. All five were resold in the 1920s, four of them to the Brunswick Lumber Company.