Register for air conditioning

A register for air conditioning, comprising:

• a register panel disposed in a vehicle passenger room, and having an outlet opening for air-conditioning air;
• and
• a cylinder-shaped retainer demarcating a ventilation passage communicated with the outlet opening of the register panel, and having an inner opposite end and a register-panel-side opposite end;
• the register-panel-side opposite end comprising at least one member selected from the group consisting of:
• a top-surface wall demarcating a top surface of the ventilation passage, and disposed movably so as to make the top surface movable between diminishing the ventilation passage and enlarging the ventilation passage adjacent to the outlet opening of the register panel;
• a bottom-surface wall demarcating a bottom surface of the ventilation passage, and disposed movably so as to make the bottom surface movable between diminishing the ventilation passage and enlarging the ventilation passage adjacent to the outlet opening of the register panel;
• and
• paired side-surface walls demarcating paired side surfaces of the ventilation passage, and disposed movably so as to make the paired side surfaces movable between diminishing the ventilation passage and enlarging the ventilation passage adjacent to the outlet opening of the register panel.