Designed to withstand punishment from the elements and the rigors of competition shooting. Flex Fletch vanes retain their form even after shots that pass through targets. Provides flexibility that dampens arrow oscillation and increases accuracy. Vane bases must be cleaned with acetone, alcohol, or Zing primer before fletching. Parabolic cut vanes available in sizes 1.75â?쳌 (3.08 gr.), 2â?쳌 (3.7 gr.), 2.5â?쳌 (4.6 gr.) 3â?쳌 (6.1 gr.), and 4.18â?쳌 (11 gr.).