It shall be unlawful for any person to be in possession of graffiti or etching tools, etching cream or slap tags on any revenue transit operated by the San Francisco Municipal Transportation Agency if the person has been convicted of or pled guilty or no contest to a crime involving the vandalism, defacement or destruction of property including a violation of California Penal Code Sections 594, 640.5, or 640.6 within the last seven years. For purposes of this Section 606:
(a) "Graffiti or etching tools" is defined as a masonry or glass drill bit, a glass cutter, a grinding stone, an awl, a chisel, a carbide scribe, an aerosol paint container, or any permanent marker with a nib (marking tip) one-half inch or more at its largest dimension and that is capable of defacing property with permanent, indelible, or waterproof ink, paint or other liquid.
(b) "Etching cream" means any caustic cream, gel, liquid, or solution capable, by means of chemical action, of defacing, damaging, or destroying hard surfaces in a manner similar to acid.
(c) "Slap tag" means any material including but not limited to, decals, stickers, posters, or labels which may be affixed upon any structural component of any building, structure, post, pole, or other facility, which contains a substance commonly known as adhesive glue.