I have a stove something similar to this stove but in much better condition (A Better 'N Bens) http://images1.americanlisted.com/nlarge/better_n_bens_woodburner_200_lexington_ohio_9610262.jpg There are two screw-out knobs at the bottom that I have no idea what they do. My thought is that it allows me to connect a blower to the stove to move the hot air from around the stove to the room more efficiently, but I can't find any mention of what these knobs do. Further, when I really have my insert hot, the paint on my mantle starts to bubble a little bit. My thought is also if I can add a blower to the stove less heat would be absorbed by the mantle. Any ideas would be appreciated. Thanks.