Hey there, chainsaw users! If your Stihl's air filter is clogged or worn out, this Hyway replacement filter is just what you need. It's brand new, unused, and comes in its original packaging – just like you'd get from a hardware store. This filter is made by Hyway specifically to fit a bunch of popular Stihl models, including the MS231, MS251, MS271, MS291, MS311, MS362C, and MS391 chainsaws. The part numbers it matches are 1141, 140, and 4400. It's manufactured in Taiwan, which is known for making quality aftermarket parts. A clean air filter is super important – it keeps dust and debris out of your engine, which helps your saw run smoother and last longer. Swapping it out is usually a quick job. Whether you're a professional logger or a weekend warrior tackling firewood, having a spare filter on hand is a smart move. Keep your Stihl breathing easy with this reliable Hyway filter!