Apacs Lethal 6 Badminton Racket (5U) Isomectric head frame - Equalizes the length of main and cross strings in the stringbed, enlarging the sweet-spot for more consistent accuracy even on off-center hits. 76 Grommets system - This single-pass grommet holes construction provides more grommet holes, creating a high-performance stringing pattern that puts 7% more durability. Hi Modulus Graphite - The Hi Modulus Graphite is adopted in both sides of the frame in order to give strength and perseverance. Whip-Slim Frame - The Whip-Slim Frame provides smaller flat surface compared with an ordinary racket for better speed, fast swing-through and the quicker maneuverability.