I used to own a 1986 L-39C and as part of the original deal I was able to get several sets of drop tanks and a set of LN-41 rocket launchers that fit the L-39 pylons as well as the MIG-21 and several other Soviet block aircraft. The launchers looked great on the plane but with the empty tubes, they looked incomplete. So I contracted with an Aircraft Mfg. Co to machine a set of 26, 13 per side, aluminum dummy tips to load into the tube ends. The pictures speak for themselves as to the end result. Each tip locks into the 2.75" / 7 cm rocket tubes with a proven engineering design and have been tested multiple times at 640 Knots and 8 G's. Each dummy tip is machined out of solid 7075 Aluminum and are powder coated. The installation is quick, simple, and secure. Position dummy nose cone at front of tube w/ front entry. Need a 36" extension for 1/2" socket wrench and socket (Harbor Freight $30). Reach in from rear of tube -and engage 5/8" bolt head and lock dummy into secure position - repeat 18 time / side ;o). To remove, reverse procedure. This set of 26 dummies are NEW - except for 1 flight test - plus multiple flights of same design and units that were flown frequently on my plane. They are in PRISTINE blemish free condition, and look better in person then even the photos indicate.