Custom build and decorate your own 13" rocket with the Explorer X-13 kit. SureFire Rockets has brought a new concept of educational rocket building to educators. The Explorer X-13 is the first in a line of rockets that gives the student control over both the look and design of his/her rocket. The Explorer does not include instructions or cut fins. You print the instructions and the fin designs from this page. There are currently 4 different fin designs to choose from with more to come! By eliminating many of the high cost associated with producing rockets SureFire Rockets is able to bring you this educational 12 pack for significantly less than any other educational kit on the market. The Explorer X-13 rocket is a Skill Level 1 rocket (ages 10 and up) and flies on standard A, B, and C size engines.