very sturdy rocket. The kit I received was missing the engine retainer. they shiped me a new one. Through the wall fins, plywood fins in this tiny rocket. streamer recovery. have flown it twice now. first flight A10-3t, 2nd flight C6-5. First flight nice and low, perfect for a park flyer. the C6-5 was an amazing flight. I only attempted it because there was almost no wind at all. it landed only a little over 100yds from the launch pad. went super high up. I added a Rocketarium metal engine retainer, and a Apogee Components ejection baffle. Great flights so far.