This is a fairly simple kit t' put together -- basic through-the-wall fin mountin' and single body tube/nose cone construction. Ahoy! This kit has a "piston"-type ejection system and since the body tube is relatively short in relation t' t' forward end o' t' tapered fins, matey, thar's really no opportunity t' use t' "zipperless design" that I favor. However, ya bilge rat, t' piston system works very well. Avast! Since t' fins are G10 fiberglass, sandin' t' edges is quite labor-intensive. Ahoy! Also, when mounting the motor tube/centerin' ring, me bucko, shiver me timbers, you need t' be VERY aware that you position the piston strap (which is epoxied t' t' motor tube) BETWEEN t' fin slots, otherwise you'll have t' sand and sand and sand t' root o' t' fin that's goin' into that slot!!!! You'll have t' add no less than 3 oz. Begad! o' nose weight to brin' t' CG forward since t' CP is 30" from t' nose and t' CG is less than 1 caliber (the length o' t' tube diameter... Avast! 4" in this case) away. Ya scallywag! Avast, me proud beauty! When I flew it, I added Greg's beeper/locator which weighs about 3 oz. and it could have used about 1 or 2 oz. Begad! Well, arrr, blow me down! more... just a suggestion. Otherwise, this kit is big, ya bilge rat, fun and impressive in t' air. Well, blow me down! Avast, me proud beauty! Have fun with it, ya bilge rat, ya bilge rat, I highly recommend it! :)