IKEA ALEFJÄLL Height Lock

If you are a taller individual and own IKEA's ALEFJÄLL office chair, chances are you occasionally lean back and stretched your arms like me. I noticed throughout my workday that the back rest height would lower no matter how tight you torque the knob down. Since I always left the backrest height on the highest I made this lock that sits under the knob. Just unscrew the knob, install this part, then screw it back in. No need to over torque it tight anymore and no need to worry about the back rest slowly sliding down!