Bat skeleton black enamel pin.
Bats are mammals of the order Chiroptera; with their forelimbs adapted as wings, they are the only mammals capable of true and sustained flight. Bats are more manoeuvrable than birds, flying with their very long spread-out digits covered with a thin membrane or patagium. The smallest bat, and arguably the smallest extant mammal, is Kitti's hog-nosed bat, which is 29–34 millimetres (1 1⁄8–1 3⁄8 inches) in length, 150 mm (6 in) across the wings and 2–2.6 g (1⁄16–3⁄32 oz) in mass. The largest bats are the flying foxes and the giant golden-crowned flying fox, Acerodon jubatus, which can weigh 1.6 kg (3 1⁄2 lb) and have a wingspan of 1.7 m (5 ft 7 in).