I use 100% gas . I may get in the habit of when ever I am having problems, I have 2 chainsaws and 2 2 cycle weed trimmers, fuel lines will be changed..
I did buy the 4 different sizes, 5 foot per size pack. It came from a USA address but I think these are China made. They were yellow in color,. No pun intended. I would just had gone to the local hardware but with the lock down and you have to call in your order , ebay was easier..