Light Brick 4.5V 2 x 4 with Removable Bulb

Reference

upn0253c01

BrickLink® #

x456c01

Light Brick 4.5V 2 x 4 with Removable Bulb (part upn0253c01) is a LEGO element. CollectORbuild's catalog records it in 8 sets, including Lighting Brick (System) and Lighting Device Pack.