Logo: modern logo
Material: ABS
Inner wall: thin with vertical ridges
Inner ribs: Between the outer ridges on the long and short side.
Inner tubes:
Flowrib / center line inside top surface: No.
Mold pip: on the stud
Mold numbers: 133 below the right tube.
Mold position numbers: 1 to 8, below the left tube AND inside one of the studs.
Intellectual property protection: None
DesignID 3001?: No
Remarkable features:
Colors known: Yellow, Black, Gray
[Original post and comments on Flickr.]