Question about lug nuts

on my real wheels (which i am getting back in october, my brother has them on his 01' GT conv in MA) i have different size lugnut on the front than on the back... this is because i have about a 2 inch offset on the back, and with the chrome lugnuts (hexagonal shape, i believe, i think they call them 'acorn shape' or something) that we put on when we got my new rims, you could not see the lugnuts at all in the back, because they were all the way in the hole, so we got newer 'extended' ones, same shape, but slightly different size (not noticable by eye, but we now need a 4 way lug wrench... thats shiny and fits in my trunk nicely...
I think we got those off ebay... or maybe got them through our 'connections'... i cant remember, theyre kinda no name brand, and are 'acorn' style (hexagonal with a rounded bump on top)

wait just one dang second, what kind of cars would use those looking thing? or are those on the opposite side... or something, because mine looks like the 'conical/tapered' but without the threads... lol???

some german cars use Lug BOLTS, but the concept is the same