These 2.75" "Test Rockets" w/ a 5minute flare inserted into the 18Lb head had 4 spring loaded fins retained at aft/trailing end that would deply once launched.
I don't recall the exact variation/model.
10each packed in hvy duty cardboard tubes in a wooden crate.
Low Alt & High Alt meteorological balloons w/ reflectors & 30minute flare attached were launched for Wind Weighting purposes & tracked by C band radar.
