← The LEGO Parts Guide

Duplo Brick 2 x 2 Pin on Side (Part 3966)

1979-2014RETIRED

Custom LEGO part image © 2025 Tom Alphin / Brick Architect.

External Links

LEGO parts are described differently on other websites and may use different part numbers.

Bricklink:
3966 Duplo, Brick 2 x 2 with Pin on Side
Rebrickable:
3966 Duplo Brick 2 x 2 Pin on Side
Brickset:
3966 DUPLO BRICK 2X2 W. SNAP
LDraw:
3966 Duplo Brick 2 x 2 with Pin on Side
 ALL YEARS
OVERALL RANK
2154
# PIECES
52(RANK: 2302)
# SETS
33(RANK: 2040)
# COLORS
5(RANK: 2273)

Ranking based on buying one copy of every LEGO set, counting the number of sets containing each part, then sorting by part and color.

Overall Rank is a weighted score combining the number of parts, sets, and colors produced.

Printable LEGO Brick Label

Requires a compatible Brother Label Printer — learn more at brickarchitect.com/labels.

Duplo Brick 2 x
2 Pin on Side
3966
.LBX

Preliminary Label: Part name may be inconsistent since this part has not been added to LEGO Parts Guide yet. (You may want to edit part name before printing.)

This part has not been added to The LEGO Parts Guide yet, so you will not find it in the galleries sorted by category.

This page was generated using data from Rebrickable, BrickLink, Brickset, and LDraw.

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The LEGO Parts Guide is a work in progress

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Check out the About the LEGO Parts Guide page to learn more about why I created this guide. It also includes a detailed version history with images of early prototypes of this guide.


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This guide uses external data from Rebrickable, BrickLink, Brickset, and LDraw.