Foxnovo Universal Anti-crash Landing Training Gear Kit Set for RC Helicopter (Blue) Color: mainly blue. Material: durable hard carbon fiber, plastic and soft sponge. High quality solid blue lightweight sponge balls with strong carbon fiber training rods. Great for beginners or experts who are trying out new RC helicopters or new set-ups. It helps balance helicopters and helps prevent blades or other expensive parts from tilting and hitting the ground or any obstacles, thus saving costly damage. Simple and practical design, easy to install and use.