K&rsquo;NEX K-FORCE  Mega Boom Building Set &ndash; 335 Pieces &ndash; Ages 8+ Engineering Education Toy 335 ASSORTED PARTS  The K-FORCE Mega Boom Building Set includes 335 KNEX pieces to use in constructing six different toy blasters and target models. This building set includes KNEX rods and connectors, plus special parts to create customized blasters: two blaster chambers, three skull dart holders, two quick-fit grips, two preload rings, and seven foam darts. DOWNLOADABLE INSTRUCTIONS  In addition to the main Mega Boom blaster, you can download instructions for five alternate blasters and buildable targets for added fun. The Mega Boom Building Set is compatible with the entire K-FORCE Build and Blast line. Combine the Mega Boom Building Set with other KNEX sets to build even bigger! OFFERS HANDS-ON LEARNING  KNEX educational models offer proactive opportunities for children to develop their creative juices by building their own dart blaster or toy gun. Get your kids away from the computer screen and let them create mentally stimulating experiences by building something that fascinates them. PEAK PERFORMANCE  Even though these blasters are designed and created by you using KNEX rods and connectors, youll see no loss in performance or durability! Darts fire up to 75 feet and special rod-locks have been added to ensure the parts stay together, even in the heat of battle! STEAMagination  This is the connection of STEAM (science, technology, engineering, arts & math) with a childs natural curiosity and creativity, and it powers the fun of each and every KNEX building set. Building with KNEX puts children on a path to a fundamental understanding of STEAM / STEM subjects. CUSTOMIZABLE BLASTERS  K-FORCE Build and Blast is the only line of dart blasters that you design, build and fully customize! Specialized parts like quick fit grips and dart launching mechanisms combine with the K'NEX building system to create any blaster that you can imagine. COMMITMENT TO QUALITY  KNEX rods and connectors are responsibly made in America at a landfill-free, zero-waste green manufacturing facility in Hatfield, Pennsylvania. We test to the strictest quality and safety standards, ensuring that your child has a successful, trouble-free building experience. PARTS GUARANTEE  Broken part? Missing part? If you need a replacement for any reason, just give us a call! Well get you what you need so that your child can get back to building as soon as possible.