The design could use some tweaks. The seat plate has a groove/bump but the chair back that is supposed to attach on it is flat so the screws don't really reach on both sides. I just got a bigger screw I had in the house but it took a while before I figured it out. Also with the seat plate it's pretty far back and has the tilt tension knob on it. You have to reach all the way back to make that adjustment when needed. Ultimately I'm happy with the chair but assembly and tilt tension adjustment keep it from top rating