When having two single coils and each are wound in an opposite direction and both have an opposite magnetic polarity towards the strings. When the pickups are combined in parallel when using a proper switch the combination of the two pickups become humbucking. In a traditional humbucking pickup the two coils are wound in the same direction and hooked up as follows:

1. The beginning of the adjustable coil is grounded.
2. The beginning of the non-adjustable coil is positive.
3. The finish of each coil in both bobbins are connected together.
4. Each bobbin has an opposite magnetic polarity.

When the pickup is hooked up properly the pickup will be humbucking and in phase. Also having two coils wound in the opposite direction and both having opposite magnetic polarity are also considered “in” phase and humbucking.