Searching for materials about Philadelphia’s trolley fleet, I happened upon a beautifully detailed, dimensioned scale drawing of a Checker Model K. Drafted by the owner, Philadelphia Rapid Transit Company, in 1930. Sometime in the 1920s PRT bought up the cab business in Philly. After a violent strike in the early ’30s and after promising concessions to the union, the PRT simply unloaded the cab business at a loss.