Alaska Railroad's 300 class locomotives were all 0-6-0 switchers.  Ten locomotives #310 - #319 were built by Lima for the US Army between Jan and March 1944  and all were transferred to the Alaska Railroad in 1946 and 1947. Weighing 160,000 lbs, they had 50 inch drivers and 21x28 inch cylinders.  All were retired in April of 1954 and went to scrap in the late 1950's.
This photo was taken in Whittier in May 3, 1948.

Alaska Railroad photo, Jack Klingbeil collection