The utility model relates to an adjustable core type reducing sealer, emitting lid, overcoat shell, reducing inner bag on including, going up blind flange, the lower flange of taking the connector and sealing member, it is porose wherein to emit lid central authorities to open on, emits on, the lid by the upper portion thread connection of internal thread with the overcoat shell, and internal thread and the external screw thread of reducing inner bag of overcoat shell are connected mutually, and the sealing member dress is inside the reducing inner bag, and the top of reducing inner bag be the arcwall face, the circular bead of the oriented outer extension in bottom, upward blind flange and take the lower flange of connector to connect the upper and lower both sides at the circular bead respectively. The utility model discloses simple structure for overcome present sealing material the change, load that the trouble wastes time and energy and the problem of pole and seal cavity wall decentraction.