2n3055-2 transistor specs

Hi, I recently came across an old power supply that had a number of transistors with "2n3055-2" marked on them and I am wondering how do they differ from the regular 2n3055 transistor. I have tried searching google but nothing comes up about the "-2" part.

Does anyone have any ideas on if this transistor is in any way different of its specs as I am curious to know.

Thanks!

Probably selected to tighter specs than a default 2N3055, most likely Hfe.

Closely matched for Hfe. In other words, it fell in group 2. When devices are paralleled, it makes sense to have them Hfe matched. The absolute Hfe doesn't matter as much as the variation.