It's an older style single coil. Before the 'strat' shape became the industry standard shape and design for single coils, most companies producing electric guitars had their own unique designs for their pickups.
Obviously as time went on and during the 70's the strat, tele, LP and their many copies became the most common guitars by an enormous margin, when the aftermarket pickup became widely available, it made sense to cater for this market in the main.
This then led to other companies using this design as their basis in order that their bodies would be able to be retrofitted.
In other words, an odd cycle occurred that phased most other designs out in favour of this new 'standardised' profile.
