← The LEGO Parts Guide › Electronics › Hub

4×8×4 Small Hub (2-Ports, 6x AAA) (Part 28738)

2018-2025CURRENT

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

The smallest of the Powered Up hubs, this one is designed to work best with System models thanks to the studded top and bottom.

It is also sometimes referred to as the "City Hub".

External Links

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

LEGO Pick a Brick:
28738 HUB NO. 4
Bricklink:
bb0892c01 Electric 9V Battery Box Powered Up Bluetooth HUB with Light Bluish Gray Bottom
Rebrickable:
28738 Hub / Battery Box, Powered Up
Brickset:
28738 HUB NO. 4
LDraw:
28738 Electric Powered Up Hub
 CURRENTALL YEARS
OVERALL RANK
-316
2604
4754
# PIECES
3(RANK: 2667)
9(RANK: 4753)
# SETS
3(RANK: 2431)
9(RANK: 3937)
# COLORS
1(RANK: 2746)
1(RANK: 6060)

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 2020-2024. (2025 not included because too few sets have been released and inventoried at this time.)

Printable LEGO Brick Label

4×8×4
Small Hub
28738
.LBX

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

A label for this part is included in the legacy LEGO Brick Labels collection.

Date Added: 2024-02-21 12:00:00

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