Strong sealing performance: the DMJJSD sealing cover of the pipe blocking cover. Fully closed design: laughing chimney cover stainless steel, inserts flush with the tube, the mounting wreath is spot-welded to the cap, when you squeeze it, you can insert it into a hole, then let go, this ring tightens itself to the inner walls of the hole, forms a tight connection to the inside of the pipe.
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