{HEAD ~ An elastically engaged portion} 67a of the operating lever 67 is elastically and selectively engaged with the U shaped engaging bar 62 of {TAIL ~ the base} 1 
{ HEAD ~ An elastically engaged portion } 67a of the operating lever 67 is elastically and selectively engaged with the U shaped engaging bar 62 of { TAIL ~ the base } 1
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH