Aerogel: Dunlop aerogel rackets incorporate the world's lightest solid, which has a strength of up to 4, 000 times its own weight. The three-dimensional nanometer-sized molecular network delivers an unmatched strength to weight ratio for enhanced stiffness and increased power. Dunlop aerogel technology and 4d braided technology creates the perfect blend of power and stability. Each premium Dunlop racket is carefully hand crafted to precise specifications by skilled craftsmen utilizing over 80 years of experience. Product description the aerogel 4d elite by Dunlop is hand made and the 4d braided technology crates the perfect blend of power an stability. The aerogel rackets incorporate the worlds lightest solid, which has a strength of up to 4, 000 times its own weight.