My 026 has run .325 x 50 ga since new on a 18" stihl bar, I got a second stihl es bar for it now which is 16" and it is 50 gauge as well..... the 18" runs 74DL if I remember correctly, I don't remember what the 16" count it, I haven't even bolted the 16" bar on yet, I don't run the 026...