As others have said: The Dexstar rim sold by E-trailer can be used on any truck as long as the load rating is not exceeded. The "K" is the profile/cross section shape of the rim. This rim will accommodate many hub cap types from the 60's. Maybe 50's. It's an exact copy of steelies used in the day. The wheel will not know if it's on a trailer or a truck. It is DOT approved. They don't exactly say it's OK for a truck for legal reasons.
You could make a case that trailer wheels need to be stronger than truck wheels (maybe not off road).

Offset? "Slightly offset" is pretty much the same as zero offset. Depending on what dimension slightly is.

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