Unilug wheels
As stated, unilug wheels are for 5x4 1/2 or 5x4 3/4. I think Rocket made a unilug wheel that fit 5x4 and 5x4 1/2, but that was probably 40 to 50 years ago. The trick to the unilug wahers is to cinch them up finger tight, making sure the washer in in the inset. Don't let the tire monkeys take your wheels off and put them back on, that is a recipe for disaster. Ask me how I know...