yonex league 7 badminton feather shuttlecock l-7,1 doz. yonex the yonex league 7 feather shuttlecocks are ideal for badminton players looking to up their game. constructed with a duck feather skirt and a cork tip, these badminton shuttlecocks are designed to deliver stable trajectories. -duck feathers offer a high level of durability -feather skirt with cork tip helps provide greater precision for stable trajectories -perfect for expert players during training or competitions