A hinge includes a leaf unit, first and second action units and an axle unit. The leaf unit includes first and second leaves that are rotatable relative to each other. The first leaf has a first barrel. The second leaf has a second barrel. The first and second action units are co-rotatable with the first leaf. The axle unit includes a fixing member mounted in the second barrel and co-rotatable with the second leaf, and first and second axle constituents respectively associated with the first and second action units and co-rotatable with the fixing member.