The viewing hole is of a predetermined size so as to preclude {HEAD ~ convection flow} sufficient to cook {TAIL ~ food}, whereby the food will cook by radiant heat only 
sufficient to cook
The viewing hole is of a predetermined size so as to preclude { HEAD ~ convection flow } sufficient to cook { TAIL ~ food } , whereby the food will cook by radiant heat only
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH