Peter, it sounds like the Ecco. The first group was made in Japan, then production was switched to El Cajon. I have both and the 2 differences are: 1) the liner is slightly stouter on the USA model. and 2)The Japan model uses AUS 6 and the USA uses 420HC steel.
The Diamondback is made in Taiwan and for the money they are good knives also.
(note: info on steel came from Bucks website last year)
guy