Where can I find a 4.5 mm chainsaw sharpening file? The manual for my 16" chainsaw states that the 3/8 pitch chain should be sharpened with a .177 (4.5 mm) diameter file. However, I can't find that size file. For example, the closest size files which come with Stihl sharpening kits are 4.0 mm files which come with the 3/8" Picco and 1/4" kits, and the 4.8 mm files which come with the .325" kit. The 3/8" kit comes with a 5.2 mm file. Where can a obtain 4.5mm chainsaw sharpening files? Does Oregon sell sharpening equipment for its chains? If I buy a Stihl sharpening kit, which one should I buy?