Just something to be aware of here. Stihl has three different bar (mounting) sizes. That's the width of the slot in the back of the bar that rides on the stud flanges. Sizes/Applications are as follows:
Small - saws up to and including the 025.
Medium - 024 to 066, but Excluding the 025. The 025 is the red-headed step child here.
Large - 055, 075, 084, 088.
The small bars are shaped differently (skinnier) than the medium bars. So if you are running a small 16" bar on an 025, the chain will be shorter than the same 16" chain on a medium bar 024.
I believe in this case it's 63 versus 67 drive links.
The point here is that if you have an 025, you need to make sure you buy a chain with the correct number of drive links. If you just buy a 16" chain, it could very well be for the larger bar used on the medium mount saws, not the small bar used on the bastard 025.
And the dumb ass behind the counter at your Stihl dealer will not be helpful enough or knowledgeable enough to help you out with this tidbit of useful trivia.
Tony Rumore
Tromix