For the most part, these covers fit the neck and middle single coil pickups in my 2012 Squier Bullet Strat AND the original pickguard very well.If they had been slightly shorter (about 14mm instead of 15mm) I would have been thrilled with these covers. Yes, 1mm does make a difference, because two of the pole pieces sit below the surface of these covers (not flush, they are below). The pole spacing was perfect (on the 50mm covers anyway, I have no use for the 52mm cover so I am not commenting on the fit of that one). The other measurements were perfect. My guitar looks great.