The MIG-21 has so many variants that it's insane. The PF stands for (translates to) Interceptor Upgraded. So this variant of the MIG-21 is MIG-21 Interceptor Upgraded. The kit is a reissue of a kit released over 3 decades ago. The kit, however has some fit issues. It still finishes to a nice kit. The price here though is really good. The kit is not up to today's new tech, but it still holds itself as one of the old school kits. It has some inaccuracies.