Seat Assembly and System

A system may include a seat assembly. The seat assembly may include a seat base, a seat portion mounted to the seat base, and an armrest assembly configured to be in an up position or a down position. The armrest assembly may include a handle operable by a user to lock or unlock at least one functionality of at least one adjustable seat assembly feature. Operation of the handle may be configured at least to: unlock the at least one functionality of at least one adjustable seat assembly feature while locking the armrest assembly from moving between the up position and the down position.