← The LEGO Parts Guide › Vehicle › Propeller, Engine, Fin & Mast

4×5×3 Engine (Part 43121)

2002-2020RETIRED

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:
43121 Engine, Large
Rebrickable:
43121 Engine, Large
Brickset:
43121 JET ENGINE 4X5X3
LDraw:
43121 Plane Jet Engine 4 x 5 x 3
 ALL YEARS
OVERALL RANK
1528
# PIECES
97(RANK: 1754)
# SETS
55(RANK: 1541)
# COLORS
8(RANK: 1377)

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.

4×5×3
Engine
43121
.LBX

Included in legacy LEGO Brick Labels collection.

4×5×3
Engine
43121
.LBX

Small QR codes are hard to scan with some devices.

Date Added: 2024-02-21 12:00:00
Date Modified: 2025-10-03 19:18:14

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