Operating Era: 1904-1937. THIS SERIES NOW COMES WITH OUR NEW ONE-PIECE ROOF FRAME. Pennsylvania RR, Pennsylvania Lines, Cleveland, Akron & Columbus, Grand Rapids & Indiana, Vandalia RR, Cumberland Valley. The KF stock car was built on the same underframe as the XL (1300 series), RF (2700 series) and XLC (5500 series) beginning in 1904. The earliest cars used the pre-1905 lettering and numbering standards but were converted by 1909. Deliveries of 1905 and later for Lines East and West met the new standards. However, controlled lines CA&C and GR&I used the old lettering standards up to at least 1910. Car built in 1909 had improved doors. 1909 also saw the first double deck cars, class KFA, for Vandalia Line. The last KFs were built in 1912 with safety appliances as were some KFAs, both for Cumberland Valley. PLEASE SEE OUR DS BOX CAR SECTION FOR OTHER XL TYPE KITS IN THE #1300 SERIES.