Function Brick Round 4 x 4 x 2/3 with 2 Studs and Black 'Aperture' Print

Reference

19981pr0005

BrickLink® #

18605c01pb05

Function Brick Round 4 x 4 x 2/3 with 2 Studs and Black 'Aperture' Print (part 19981pr0005) is a LEGO element. CollectORbuild's catalog records it in 1 set, including Portal 2 Level Pack.