Yep many newer hydros have the "internal Expansion tank" So it requires the 2 barb fitting (So it can vent while filling) in the You Tube I posted from H-G. https://www.hydro-gear.com/oil/
My Scag has them & my fitting is ready & waiting..
I only use Amsoil Saber in tin foil packs for perfect mix for 1 gal. made such an improvement. I had to turn down idle speed a bit. On 100% gas. Can no longer get 100% in 93 TIKO here....
But spark arrestor screens stay clean etc.
Mug is known for its smooth, creamy flavor, while Barq’s has a more intense root beer taste. Mug is caffeine-free, while Barq’s has a small amount of caffeine.
Mug, as I don't do caffeine..