Flying squirrels are not capable of powered flight like birds or bats; instead, they glide between trees. They are capable of obtaining lift within the course of these flights, with flights recorded to 90 meters (295 ft). The direction and speed of the animal in midair is varied by changing the positions of its two arms and legs, largely controlled by small cartilaginous wrist bones. This changes the tautness of the patagium, a furry parachute-like membrane that stretches from wrist to ankle. It has a fluffy tail that stabilizes in flight. The tail acts as an adjunct airfoil, working as an air brake before landing on a tree trunk.