When {HEAD ~ the tool} is applied to {TAIL ~ a fastener}, a bias load is applied along the axis of the tool and the drivetrain assembly 71 translates rearward compressing the spring and contacting the pushbutton 
When { HEAD ~ the tool } is applied to { TAIL ~ a fastener } , a bias load is applied along the axis of the tool and the drivetrain assembly 71 translates rearward compressing the spring and contacting the pushbutton
OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH