The last day of Defender of Velayat Skies Drills. The drills started on Monday and lasted for four days. All branches of Iran’s armed forces participated in these drills, in an area of 850,000 square kilometers, making it the biggest aerial defense drill in Iran’s history. Some of Iran’s most advanced weapons were put to the test in these drills. One of the weapons tested was an optimized version of the S-200 missile, made by Iranian engineers. Brigadier General Shahrokh Shahram, the spokesman of the drills told us more about the missile and today’s program.