The present invention comprises one set of {TAIL ~ drive gears} and one set of driven gears which are in {HEAD ~ a constant mesh position} 
The present invention comprises one set of { TAIL ~ drive gears } and one set of driven gears which are in { HEAD ~ a constant mesh position }
OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD