Starting in 1973 the Japan Air Self-Defense Force received 154 F-4EJ Phantoms that were based on the USAF F-4E. 138 of these aircraft were manufactured under license by Mitsubishi who produced the last F-4 Phantom II. Several changes were made to the F-4E to make it an F-4EJ. Basically it had any offensive weapons removed but eventually these restrictions were lifted and the aircraft were updated with missiles and the latest electronic equipment.
The squadron emblem of the 301st Squadron is a frog wearing a scarf with 7 stars representing the 7th Air Wing. The mascot is based on a frog found locally near the Hyakuri AB. F-4EJ Kai 17-8440 was the last Phantom delivered in the world and arrived on May 20, 1981. It is assigned to 301st Squadron, the last JASDF F-4 squadron. The 301st is scheduled to retire the F-4 in 2021 and move to Misawa AB and convert to the F-35.