New size, seeing on 346XP, 450's and a few other Husqvarna products with 20" bars using. 325 pitch chain. Chain Size 325 Pitch. 050 Gauge 80 Drive links.325 Pitch. 050 Gauge 80 Drive links. Look on your bar, near the engine and you should see chain specification on the bar as to what the pitch, gauge and drive link count are to be for your saw.
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