The application discloses a magnetic pole assembly having a pole tip arranged in a magnetic flux path and side shields separated from the pole tip by non-magnetic gap regions. The side shields are shaped to provide a differential shielding effect alongside the pole tip. As described, the sides shields are shaped to provide a non-magnetic gap region having a width that increases in the downtrack direction along a length of the pole tip. The increasing non-magnetic gap region alongside the pole tip provides a smaller non-magnetic gap region separating the pole tip from the side shields at the leading edge than the non-magnetic gap region separating the pole tip from the side shields at the trailing edge of the pole tip.