the filter shown in the drawings has a bottom , which , is shaped as a frustum of cone - and a top part 2 which is cylindrical . the part ( 1 ) is provided with a series of holes roundly placed , while the part ( 2 ) is provided with the edge or flange portion 3 which has holes 4 on its surface . it is clear that the filter can be placed , at the end of the cigarette , or in the very filter of a filter cigarette , or linked with any non - filtered cigarette . the part ( 1 ) is pushed into the mouth of the cigarette ; the part ( 2 ), also pushed into the cigarette , leaves , in the cigarette edge , a part thereof which is just a little greater then the diameter of the cigarette , so as to create a perfect sealing of the cigarette mouth . the filter according to the known invention has all the advantages of the filters , without , however having the disadvantage of an external filter which has nothing to do with the cigarette . the filter can be provided within its interior with baffles or filtrating materials or with any other suitable filtrating system . it possible to use the filtrating system which cannot be used with paper filters or with any other filter types utilized in industry . the filter adjustment is extremely simple does not need expensive and cumbersome and unaesthetic cigarette holders containing filters ; aesthetically the cigarette appears to have no filters . the lack of any cigarette holder permits to avoid the touch of the smoker &# 39 ; s teeth with it , which has proved to be very harmful . the filter can be pulled out , if a smoker wants in order to be fitted in a new cigarette . furthermore , in a possible modification the shape of the bottom the filter can be changed . this bottom can be shaped as a frustum of a pyramid or as a rigid spring provided with holes along its length . such holes in the filter can be replaced by slits or openings of any form . it will be understood that each of the elements described above , or two or more together , may also find a useful application in other types of cigarette filters differing from the types described above . while the invention has been illustrated and described as embodied in a cigarette filter , it is not intended to be limited to the details shown , since various modifications and structural changes may be made without departing in any way from the spirit of the present invention . without further analysis , the foregoing will so fully reveal the gist of the present invention that others can , by applying current knowledge , readily adapt it for various applications without omitting features that , from the standpoint of prior art , fairly constitute essential characteristics of the generic or specific aspects of this invention .
a filter applicable to a cigarette and fitted therein by a user includes an elongated part fitted in a mouth provided in a cigarette and a flange which seals the cigarette mouth when the elongated part is inserted thereinto .