Probably the cool tough macho truck label on the bottle. I am using QTP 4X4 oil in my 4 Runner...it had a cool 4x4 on the label. I am afraid to use it in my car.
Note: I am only using the 4x4 oil because WM had it on closeout for $9 for a 5qt jug and I got a $10 rebate on it.
From M1 site: "It contains extra anti-oxidant, which can provide greater protection against deposit formation in hard-working gasoline trucks, vans, SUVs and recreational vehicles."