Tygon is the brand name for the plastic hose that seems to be the most common hose used on chainsaws,weedeaters etc.
I repaired 2 used weedeaters and a leaf blower given to me that the hoses were cracked on. That is all that was wrong with them.
In this US Plastics/Tygon attachment, there is no mention of being compatible with Ethanol fuel, which these days is a must.
So it seems like this type of hose needs replacing every few years, thats the way it is.
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