This is part 3 o' 3 o' me review o' t' Estes Tandem-X launch set. Avast, me proud beauty! In this part, ya bilge rat, I do a complete build o' t' Crossfire ISX with tips along t' way for this Skill Level 1 rocket. Begad! It can be launched on A,B,and C engines. Begad! At t' end o' t' video, I launch it on an A8-3 and also a B6-4. Ahoy! Great flights both times.