This mold was possibly first used in regular production, but I have not found any corresponding bricks yet. The uncommon mold pip location and the missing pat pend mark might indicate that this mold was special from the start.
This test mold was used by BASF.
Logo: Wide straight O
Material: ABS
Wall type: Thick
Inner ribs: none
Inner tubes: yes
Flowrib / center line inside top surface: No
Mold pip: on stud
Mold position numbers: Scratched roman numerals I to X.
Intellectual property protection: None
Colors known: Both LEGO colors and non-LEGO colors.
Remarkable features:
- Mold pip on the stud
- Missing pat pend mark
- Mold number I has a line inside the center tube. Mold number VI has a cross (+).
UNANSWERED QUESTIONS
- Was this mold ever used for regular production, or was it constructed as a special test mold?
[Original post and comments on Flickr.]