The body has a base, a rear cover, a front cover, {TAIL ~ a bearing seat} and {HEAD ~ a middle liner ring} 
The body has a base , a rear cover , a front cover , { TAIL ~ a bearing seat } and { HEAD ~ a middle liner ring }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD