An instrument is provided for working of surfaces of parts inside engineered cavities by means of a tool, with the possibility of simultaneous viewing of {TAIL ~ the site} of {HEAD ~ the working operation} 
An instrument is provided for working of surfaces of parts inside engineered cavities by means of a tool , with the possibility of simultaneous viewing of { TAIL ~ the site } of { HEAD ~ the working operation }
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 TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD