The pelvic limb muscles of emus contribute a similar proportion of the total body mass as do the flight muscles of flying birds.[34] When walking, the emu takes strides of about 100 cm (3.3 ft), but at full gallop, a stride can be as long as 275 cm (9 ft).[35] Its legs are devoid of feathers and underneath its feet are thick, cushioned pads.[35] Like the cassowary, the emu has sharp claws on its toes which are its major defensive attribute, and are used in combat to inflict wounds on opponents by kicking.[36] The toe and claw total 15 cm (6 in) in length.[35] The bill is quite small, measuring 5.6 to 6.7 cm (2.2 to 2.6 in), and is soft, being adapted for grazing.[32] Emus have good eyesight and hearing, which allows them to detect threats at some distance.[37]