Sturdy Design: Features a unique concave-convex buckle system for stable structures, avoiding weak connections. 260-Piece Set: Includes 88 blocks, 110 tubes, and accessories to build houses, castles, rockets, and more. Safe & Durable: Made of non-toxic ABS plastic, odor-free, and safe for kids (ages 3+). STEM Learning: Encourages creativity, problem-solving, and hands-on skills with an included idea booklet. Fun & Interactive: Colorful tubes and marble runs add excitement compared to basic building sets. Ideal Gift: Perfect for birthdays, holidays, or as an educational toy for boys and girls. Great for fostering imagination while ensuring durability and safety!