An armrest comprising: an armrest subframe configured to couple to a seat or an arm of the seat comprising: a coupler configured to attach the armrest subframe to the seat or arm of the seat; and a slot within a face of the armrest subframe configured to receive a stop pin; an arm pad operatively coupled to the armrest subframe and configured to slide alongside the armrest subframe, comprising: a plurality of grooves formed on one edge of the armrest subframe; the stop pin, wherein the stop pin restricts the translation of the arm pad along the armrest subframe, wherein the slot and stop pin arrangement prevents the arm pad from extending or retracting too far relative to the armrest subframe and releasing from the armrest subframe; a spring anchor disposed on the arm pad; and a lever comprising: a fulcrum rotationally coupled to the armrest subframe; a lock end comprising a locking pin configured to engage one or more grooves of the plurality of grooves; and an actuating end; wherein a movement of the actuating end at least one of engages or disengages the lock end from the one or more grooves of the plurality of grooves; wherein an extension spring is coupled to the spring anchor and the lever is configured to bias the locking pin against the one or more grooves and bias the arm pad; wherein if the arm pad is locked into an extended position relative to the armrest subframe, the extension spring is extended; by pressing the actuating end and disengaging the locking pin, the extension spring contracts, providing a motive force that translates the arm pad into a retracted, home, or near-home position. an armrest subframe configured to couple to a seat or an arm of the seat comprising: a coupler configured to attach the armrest subframe to the seat or arm of the seat; and a slot within a face of the armrest subframe configured to receive a stop pin; a coupler configured to attach the armrest subframe to the seat or arm of the seat; and a slot within a face of the armrest subframe configured to receive a stop pin; an arm pad operatively coupled to the armrest subframe and configured to slide alongside the armrest subframe, comprising: a plurality of grooves formed on one edge of the armrest subframe; the stop pin, wherein the stop pin restricts the translation of the arm pad along the armrest subframe, wherein the slot and stop pin arrangement prevents the arm pad from extending or retracting too far relative to the armrest subframe and releasing from the armrest subframe; a spring anchor disposed on the arm pad; and a plurality of grooves formed on one edge of the armrest subframe; the stop pin, wherein the stop pin restricts the translation of the arm pad along the armrest subframe, wherein the slot and stop pin arrangement prevents the arm pad from extending or retracting too far relative to the armrest subframe and releasing from the armrest subframe; a spring anchor disposed on the arm pad; and a lever comprising: a fulcrum rotationally coupled to the armrest subframe; a lock end comprising a locking pin configured to engage one or more grooves of the plurality of grooves; and an actuating end; wherein a movement of the actuating end at least one of engages or disengages the lock end from the one or more grooves of the plurality of grooves; wherein a fulcrum rotationally coupled to the armrest subframe; a lock end comprising a locking pin configured to engage one or more grooves of the plurality of grooves; and an actuating end; wherein a movement of the actuating end at least one of engages or disengages the lock end from the one or more grooves of the plurality of grooves; wherein an extension spring is coupled to the spring anchor and the lever is configured to bias the locking pin against the one or more grooves and bias the arm pad; wherein if the arm pad is locked into an extended position relative to the armrest subframe, the extension spring is extended; by pressing the actuating end and disengaging the locking pin, the extension spring contracts, providing a motive force that translates the arm pad into a retracted, home, or near-home position.