Oklahoma Joe's Highland Offset Reverse Flow Offset Charcoal Smoker and Grill With 1093 sq. in. Cooking Area in Black. LARGE-SCALE COOKING CAPACITY: Unlike other charcoal grills, this grill has 619 sq in primary and 474 sq in secondary grates smoke up to 5 briskets, 10 chickens, or 7 pork shoulders, plus a 281 sq in firebox grate for grilling wings or burgers.