The Caledonian Railway 439 Class is a class of 0-4-4T steam locomotive. It was a development of earlier Caledonian Railway 0-4-4T locomotives, including the 19 Class and 92 Class, and predecessor of the 431 Class. The 439 Class was introduced by John F. McIntosh in 1900 and a modified version was introduced by William Pickersgill in 1915.