The Kodiak hunter was introduced mid year 1967 and the 67 was a 58" bow.In 68 it became a 60" bow and stayed that way Stabilizer insert was added in 1970 or 71.. 68 and 69 can be confirmed with ser # starting with 8 or 9. 72 I believe was the start of the green maple and the raised button. There are a few color variations after that with stripe colors and overlay colors but I am guessing beyond that point