{HEAD ~ The threshold force} is adjustable by changing the axial position of {TAIL ~ the compression spring seat} 
{ HEAD ~ The threshold force } is adjustable by changing the axial position of { TAIL ~ the compression spring seat }
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL