Cincinnati Dial Type Millers - late models Operation Manual
Cincinnati Last Model of "Dial Type" Milling Machines Nos. 2, 3, 4, 5 and 6 and also as Types: 315-15, 415-15, 420-16 and 520-16 (Model LL) and 520-20, 540-20, 620-20, 640-20 (Model ELA). These models had a speed dial on the column and a feed dial on the side of the knee. Operator's Instruction Book.