It’s .3/8” vs .404” saw chain?

[Maintenance supervisor]

The XL-12 had .404 as an option also.
I have and old 37cc craftsman brushcutter and it's awesome with those new circular saw tyoe blades, flies threw 3" stuff.

 

[Huskybill]

I switched because the 404” tooth is longer over the 3/8” it lasts longer.