{HEAD ~ A working piston} reciprocates in one cylinder and is conventionally attached to {TAIL ~ a crankshaft} by means of a connecting rod and crankpin 
{ HEAD ~ A working piston } reciprocates in one cylinder and is conventionally attached to { TAIL ~ a crankshaft } by means of a connecting rod and crankpin
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH REL REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH