Double-side opening armrest with external key structure

The invention provides a double-side opening handrail with an external key structure, which comprises a supporting assembly component, a fixed coating component, a pressing operation component, a movable coating component, a bearing transmission component and a linkage locking component, and is characterized in that a pair of limiting hook bodies with limiting interfaces are arranged on a supporting bottom frame of the handrail; a fixed wrapping assembly capable of being provided with an operation button is arranged at one end of a supporting bottom frame, a turnover movable wrapping assembly is arranged at the other end of the supporting bottom frame, a steering ejector rod drives a transmission sliding block to move through a bearing end column, and the transmission sliding block drives a locking end column to move through a primary connecting rod, a secondary connecting rod, a linkage sliding block and a linkage pinch bar. The outer ends of the locking end columns penetrate through the limiting protruding