The middle toe (excluding talon) can vary from 38.3 to 53.8 mm (1.51 to 2.12 in), with the hallux-claw (the talon of the rear toe, which has advanced to be the biggest in accipitrids) measuring from 24.1 to 33.6 mm (.95 to 1.32 in) in duration. In the conventional scientific strategy of measuring wing dimension, the wing chord is 325.1-444.5 mm (12.80-17.50 in) lengthy.