Brass humbucker mounting base plate with 15mm long legs.
The rule of thumb is that if the string spacing is less than two inches or 50mm, a standard humbucker is a right choice. For string spacings larger than two inches or 50mm, step up to an F-spaced or Trembucker pickup size. Due to the magnetic field created by the polepieces, it’s not absolutely necessary for the strings to pass exactly over the center of the polepieces. However, it’s a good idea to keep the E strings from sitting completely outside of the outer polepieces, as the reduced magnetic force could have a negative impact on your tone.