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Sensor, Light, 4.5V
Part

Sensor, Light, 4.5V

Reference
upn0178
BrickLink® #
x1161cx1

Sensor, Light, 4.5V (part upn0178) is a LEGO element. CollectORbuild's catalog records it in 5 sets, including Optosensor and Optosensors (4.5V) and Discs.