Bricks and Lights 11009 | Classic | Buy online at the Official LEGO® Shop US
Duplo Light Brick 51409! The greatest LEGO piece of all... ever! - YouTube
BrickLink - Part 52189c01 : LEGO Duplo Siren with Light and Sound, 1 x 2 Base with Yellow Button and Trans-Dark Blue Light Covers [DUPLO, Vehicle] - BrickLink Reference Catalog
LEGO DUPLO BLUE NUMBER 1 BRICK REPLACEMENT LIGHT BLUE NUMBER | eBay