This is a very fun motor for your 24mm rockets that need a little bit more kick off the pad, or if you just want to fly your rockets higher and faster. The liftoff speed is noticeably faster than that of an Estes E9, and the flame is huge, with lots and lots of smoke! The instructions are not terribly difficult to interpret, but if you need a more visual guide to assembling the motor, see the 3D assembly video here: http://www.flickr.com/photos/75773285@N07/7607242174/ The delay assembly is slightly different (shorter delay grain and includes the use of delay grain adapter) because it shown an E18-4W, but it's still extremely helpful in assembling the motor. The assembly is not difficult, but the one thing you need to watch out for is getting the igniter where it's supposed to go. The reason I gave this product 4 stars instead of 5 is that the copperhead --or crapperheads as the guys at my local field call them-- igniters can be difficult, and are easy to accidentally short out. The has nothing to do with HobbyLinc, by the way, it's entirely the decision of Aerotech. I would definitely recommend this motor, as well as extra igniters. The longer ones that say they are for larger motors are easier to work with than the ones that are listed as being for D-F 24mm reloads. (http://www.hobbylinc.pro/htm/aro/aro89893.htm) If your launch setup includes leads with toothed aligator clips, the Interlock igniter clip is extremely helpful as it prevents the teeth from biting through the foil and shorting the igniter. (http://www.hobbylinc.pro/htm/aro/aro89341.htm) When the igniters work, these motors are great!

This one of my favorite reloads! You get a lot of bang for your buck, especially with HobbyLinc's excellent pricing! As it says in the title, these puppies are a bit louder than expected. Noticeably more so than the single use E20. A definite crowd pleaser. They give a good kick in the pants to a regular 24mm motor mount Estes style rocket. More noise + faster speed = more fun! The only Con would be to take care when using the supplied Copperhead igniter. I would suggest getting one of the special Interlock Igniter clip made by Aerotech (ARO89341). Alligator clips with teeth can damage the igniter, shorting it out. Also I suggest reading the instructions while you build them! I have built dozens of dozens over the years... but mistakes can happen!

Excellent item i have launched over 5 rockets with these motors and all have flown great and had flawless ejection charges as well. Instructions are well written and explained. Just make sure you read all instructions before attempting your first reload process. No ignitor problems or ignition problems with any launch However make sure you are using a 12 volt launch system to ensure proper ignition of the propellant grain. PRO'S Easy to use after learning procedure for reloading long shelf life Reliable launch's Loud on take off (personal like) CON'S Lots of small parts not for children easier to reload at home rather then field