You NEED to use non-ethanol gas, but it doesn't have to be premium. Premium is OK though. You can identify a 3-ring piston engine by taking off the under-deck muffler and looking at the piston thru the exhaust ports as you rotate the flywheel. You can count them. You really, really really should use 2-cycle oil. Not sae 30 automotive oil.
I'm sticking with the 2 cycle oil . I think its better oil, makes the mower last longer. Thanks All