Micro torsion springs offer resistance to externally applied forces when the legs are rotated in angular deflection. The wire itself is subjected to bending stresses rather then torsional stresses as might be expected from the name. These springs are typically closed wound and will reduce in diameter and increase in length as they are deflected. The designed must consider the effects of friction and arm deflection on the torque. Arm lengths are regulated and space between the coils can reduce friction.