Duplo Brick 2 x 2 - Grooved Pin on Side

Reference

22881

Duplo Brick 2 x 2 - Grooved Pin on Side (part 22881) is a LEGO element. CollectORbuild's catalog records it in 27 sets, including 3in1 Dinosaurs on Wheels and 3in1 Space Shuttle Adventure. It has been produced in 3 different colors.