If you have the misfortune of having a monkey work on the wheels, the cap can get deformed such that the socket won't fit all the way to the shoulder. From then on, the cap gets increasingly damaged each time it is used. Throw in lug nuts torqued to well beyond the specs, enough so that my air impact wrench could not break them free, and you have a recipe for being stranded if you get a flat. Eventually the cap can spin independently from the nut underneath. I had to use my mallet to hammer the impact socket onto the nut in order to remove a few of them. Removing the socket afterward was a challenge, to say the least, and the nut was at that point no longer fit for purpose. I ended up breaking all 20 loose and torquing them to spec, with 5 turning into paper weights. Didn't think of looking for single piece ones until more recently, and spent $72 at the local JLR dealer for a set of 5 - didn't want to drive around with 4 nuts per wheel. I have a few now where my 6-point impact socket won't fit, but my 12-point non-impact will, so I'm trying to plan ahead and have a few nuts on hand.