Fuji electric dealer wtb business – AR22-22mm diameter illuminated pushbutton with emergency stop. The AR22 Series now uses a release arm with a wedge mechanism. This enables you to mount or remove the operator and contact block without using any tools. When fitting to a panel, you can ignore the thickness. The improved locking nut is capable of mounting the operator in both 22.3mm and 25.5mm diameter panel cutout holes.