← The LEGO Parts Guide › Curve › Arch

1×2 Half Arch, Inverted (Part 78666)

2021-2025CURRENT

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.

LEGO Pick a Brick:
78666 BRICK 1X2, OUTSIDE HALF ARCH, NO. 1
Bricklink:
78666 Arch 1 x 2 Inverted
Rebrickable:
78666 Brick Curved 2 x 1 with Inverted Cutout
Brickset:
78666 BRICK 1X2, OUTSIDE HALF ARCH, NO. 1
LDraw:
78666 Arch 1 x 2 x 1 Inverted
 CURRENTALL YEARS
OVERALL RANK
+58
177
403
# PIECES
1404(RANK: 205)
1404(RANK: 422)
# SETS
277(RANK: 232)
277(RANK: 591)
# COLORS
23(RANK: 149)
23(RANK: 284)

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.

Printable LEGO Brick Label

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

1×2 Half
Arch, Inv.
78666
.LBX

Included in legacy LEGO Brick Labels collection.

1×2 Half
Arch, Inv.
78666
.LBX

Small QR codes are hard to scan with some devices.

Date Added: 2024-02-21 12:00:00
Date Modified: 2025-09-23 16:44:30

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