If {HEAD ~ the handle} and barrel are molded as {TAIL ~ a single piece}, there may not be a need for a casing as shown in FIGS 2 and 2B. A casing 4 surrounds or envelopes the barrel 3 to keep the parts and components in place and to keep the diameter of the outside surface of the device uniform 
If { HEAD ~ the handle } and barrel are molded as { TAIL ~ a single piece } , there may not be a need for a casing as shown in FIGS 2 and 2B. A casing 4 surrounds or envelopes the barrel 3 to keep the parts and components in place and to keep the diameter of the outside surface of the device uniform
OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL 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 OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH