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Duplo Brick 2 x 4 x 2 Rounded Ends and Mouse Ears [Plain] (Part 39921)

2025NEW

LEGO part image from BrickLink.

External Links

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

LEGO Pick a Brick:
39921 DESIGN BRICK, 2X4X2, NO. 1
Bricklink:
39921 Duplo, Brick 2 x 4 x 2 Rounded Ends and Mouse Ears
Rebrickable:
39921 Duplo Brick 2 x 4 x 2 Rounded Ends and Mouse Ears [Plain]
Brickset:
39921 DESIGN BRICK, 2X4X2, NO. 1
LDraw:
39921 Part not found on LDraw.
 CURRENTALL YEARS
OVERALL RANK
3377
9059
# PIECES
1(RANK: 3102)
1(RANK: 8206)
# SETS
1(RANK: 3102)
1(RANK: 8206)
# COLORS
1(RANK: 3102)
1(RANK: 8206)

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.

Current ranking based on sets released between 2021-2025.

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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