What is this strange and possibly old white 2x4 brick?

Question

I've got 6 or 8 white 2x4 bricks. But they seem to be rather old as there is a "Pat. Pending" on it and also a "C5".

They also have one small hole on each of its sides (but none on top) and the interior is transparent.

Does anyone know from which set this comes?

score 11 · Accepted Answer · answered Feb 04 '24 at 15:10

11

answered Feb 04 '24 at 15:10

Alex

1

...and they go together with wheels like these. – noughtnaut Feb 06 '24 at 12:45
@noughtnaut this brick is not limited to wheels like these. There are more elements that go together. – Alex Feb 06 '24 at 16:43
Yup. That was intended merely as an example for people who've never seen this brick before. – noughtnaut Feb 07 '24 at 11:57

1 Answers1