A toothed front side forced by {HEAD ~ the spring force} into engagement with {TAIL ~ the ratchet wheel} in the box end 
A toothed front side forced by { HEAD ~ the spring force } into engagement with { TAIL ~ the ratchet wheel } in the box end
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH