# UL 94 UL 94 classifies flammability behavior of plastic materials under specified tests. `V-0` or `94V-0` on a circuit board is a material/compliance marking, not ordinarily the model number of the finished device. ## Notebook evidence - [[Scanned_20260730-1230#PDF Page 26|PDF page 26]] — Unidentified Blu-ray/DVD board notation. - [[Scanned_20260730-1230#PDF Page 32|PDF page 32]] — Mackie Onyx Blackjack component record. The reversed-UR Recognized Component mark may have been transcribed as “RU.”