To adjust the handle torque (handle turning pressure), to stop an annoying leak or to strip down for cleaning, follow these simple steps :
Remove the union to expose the end of valve with recesses in the exposed face. Pull the blue handle away from the valve to detach it completely
The top surface of the handle has 2 protrusions that act as the 'key.'
Pull the blue handle away from the valve to detach it completely. Insert the handle and turn clockwise to tighten, or anti-clockwise to loosen the central fitting
You can remove the whole fitting to access and remove/replace the white e.p.d.m. seal and even the ball. It is the e.p.d.m. seal and its contact with the ball that determines the handle torque.