This is the RealFlight Expansion Pack 4 from Great Planes. FEATURES: Adds 12 new airplanes, 4 new helicopters and 4 new flying sites Compatible only with RealFlight G3 and above software INCLUDES: Airplanes; Top Flite B-25J Mitchell Great Planes Yak 54 Great Planes deHavilland Mosquito MiG 15 ElectriFly Headwind B Python Biplane Hughes H1 Racer Stits Sky Baby Goldberg Tiger 2 Hobbico UpStar Great Planes Revolver Great Planes Spitfire Thunder Tiger Mini Titan Helicopters; HeliMax MX450 XS CH-46 Sea Knight Micro Heli Robinson R-22 PhotoField Sites; College Park PhotoField 3D Kemp R/C Field 3D Obstacle Course 5 PhotoField-Tarmac (full scale airport) REQUIRES: Minimum System Requirements; Realflight Generation 3 or above software Minimum; 500 MB hard drive space Intel Pentium 1.0 GHz or equivalent DirectX 9 (or above) feature-compatible video and sound card 3D accelerated video card with 32 MB (or more) RAM 256 MB Ram Optimum System Requirements; Intel Pentium 3.0 GHz or equivalent 3D accelerated video card with 128 MB (or more) RAM 1 GB RAM