Rather, the flow hole 250 maybe implemented as any suitable flowpath connecting the two filters 218,220, including, for example, a rubber or reinforced hose or {TAIL ~ elongated channel} or {HEAD ~ ductwork} 
Rather , the flow hole 250 maybe implemented as any suitable flowpath connecting the two filters 218,220 , including , for example , a rubber or reinforced hose or { TAIL ~ elongated channel } or { HEAD ~ ductwork }
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 TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD