(under subclass 34) Apparatus in which the member surrounding the material retaining element is foraminous or apertured and there is provided additional means whereby the apertures or foraminae are varied in size and/or number.
(1) Note. So-called packages of vaporizable substances provided with means to cover and uncover the openings of the package to commence diffusion are placed here and in the indented subclass as originals or cross references.
SEE OR SEARCH CLASS
206, Special Receptacle or Package, appropriate subclasses for special packages and receptacles for other than diffusible substances.
