Kensington SD2400T Review 2026 - Specs, Pros & Cons

Name: Kensington SD2400T Thunderbolt 3 Dual 4K Nano Dock
Brand: Kensington
SKU: K38390NA

The Kensington SD2400T is a compact Thunderbolt 3 desk dock from 2019. It connects through the included 0.7m Thunderbolt 3 cable and gives a compatible Mac or Windows laptop two DisplayPort 1.2 outputs, Gigabit Ethernet, three USB-A ports, one USB-C port, and a headset jack. Kensington rates it for two 4K displays at 60Hz or one 5K display at 60Hz, with up to 40Gbps shared Thunderbolt bandwidth. The dock has a 135W power adapter and sends up to 85W to the connected laptop through USB Power Delivery 3.0. That is enough for many 13 to 15-inch notebooks, although a laptop that normally needs more than 85W can charge more slowly under a heavy load. It is a true Thunderbolt 3 dock, not a regular USB-C dock with a USB-C-shaped connector. A USB-C laptop without Thunderbolt 3 cannot use it. The SD2400T is now an older model, and Amazon lists the US version as temporarily out of stock. Its layout still makes sense for a DisplayPort-based desk, especially if a compact dock that can mount behind a VESA display matters more than USB4, HDMI, card readers, or 2.5GbE networking.

Pros & Cons

What We Like

Two DisplayPort 1.2 outputs support dual 4K@60Hz on a compatible Thunderbolt 3 laptop
85W USB Power Delivery can run and charge many laptop workstations from one cable
Compact housing has VESA mounting holes for a cleaner desk setup
Gigabit Ethernet, combo audio, USB-A, and USB-C cover basic desk peripherals
Three-year limited warranty is better than the coverage on many small docks

What Could Be Better

Works only with Thunderbolt 3 hosts, not ordinary USB-C laptops
Workaround: Choose a USB-C Alt Mode or DisplayLink dock if the laptop does not have Thunderbolt 3, Thunderbolt 4, or USB4 compatibility.
No HDMI output, card readers, downstream Thunderbolt, or 2.5GbE
Workaround: Use DisplayPort monitors or active adapters, or choose a newer dock with the ports needed at the desk.
USB data ports top out at 5Gbps
Workaround: Use a newer Thunderbolt 4 or USB4 dock if fast external SSD performance through USB-C is a priority.
85W host charging is below the demand of some performance laptops
Workaround: Keep the laptop's original charger connected for high-load work, or select a dock with a higher verified charging ceiling.
Amazon lists the US model as temporarily out of stock
Workaround: Check reputable clearance or used listings carefully, including return terms and the included 135W power adapter.

Display Support

Max Displays: 2

1 display (Kensington lists one 5K display at 60Hz through the DisplayPort 1.2 outputs on a compatible Thunderbolt 3 host.)

5120x2880 @ 60Hz

2 displays (Kensington lists two 4K displays at 60Hz through the two DisplayPort 1.2 outputs on a compatible Thunderbolt 3 host. Mac display count still depends on the Mac model.)

3840x2160 @ 60Hz

Ports & Connectivity

USB Ports

3x USB-A 3.1 7.5W

1x USB-C 3.1 15W

Video Outputs

2x DisplayPort 1.2

Network

1x Ethernet (1 Gbps)

Audio

1x 3.5mm combo

Full Specifications

General
Manufacturer	Kensington
Model	K38390NA
Release Date	2019-07
MSRP	$279.99
Connectivity
Host Connection	Thunderbolt 3
Max Data Rate	40 Gbps
Driver Required	No (native)
Display Output
Max Displays	2
1x Display	5120x2880 @ 60Hz (Kensington lists one 5K display at 60Hz through the DisplayPort 1.2 outputs on a compatible Thunderbolt 3 host.)
2x Display	3840x2160 @ 60Hz (Kensington lists two 4K displays at 60Hz through the two DisplayPort 1.2 outputs on a compatible Thunderbolt 3 host. Mac display count still depends on the Mac model.)
Ports (6+ total)
USB-A 3.1	3x (7.5W)
USB-C 3.1	1x (15W)
DisplayPort 1.2	2x
Ethernet (RJ45)	1x 1 Gbps
Audio (3.5mm-combo)	1x
Power
Power Input	DC-barrel
Laptop Charging	Up to 85W

Compatibility

Windows (7+)

Amazon lists Windows 7, 8, 8.1, and 10 laptops equipped with Thunderbolt 3. Use a current supported Windows release and Thunderbolt software for best results.

macOS (10.14+)

Amazon lists macOS 10.14 or later on MacBooks with Thunderbolt 3. The dock does not bypass the native external-display limit of the connected Mac.

Known Issues

USB-C laptops without Thunderbolt 3

The dock cannot connect as a regular USB-C dock

Base Apple Silicon MacBooks with one native external display

Only one external display may work

HDMI-only monitor setups

The dock has no HDMI output

Laptops requiring more than 85W while docked

Charging may be slower under load

6.7 /10

Our Verdict

Good

The SD2400T remains a sensible used or clearance pick for someone with a Thunderbolt 3 laptop and two DisplayPort monitors. It is small, driverless for normal dock functions, has a proper 85W charging budget, and carries Kensington's three-year limited warranty. The VESA mounting holes are useful when desk space is tight. Amazon's listing held a 4.3 out of 5 rating from 36 global ratings during this review, but the product was temporarily out of stock. Its age shows in the port list. The dock has no HDMI, card readers, downstream Thunderbolt port, 2.5GbE, or high-speed USB-C data port. All three USB-A ports and the USB-C port are USB 3.1 Gen 1 at up to 5Gbps. Independent hands-on reviews from The Gadgeteer and MacSources found setup simple and reported stable use with monitors, storage, Ethernet, audio, and peripherals. The Gadgeteer also found that the front USB port is the better choice for charging a higher-draw tablet, while the rear USB ports have lower output. Buy it only at a clear discount if your computer has Thunderbolt 3 and your monitors use DisplayPort. Do not buy it for a USB-C-only laptop, a base Apple Silicon MacBook that supports only one native external display, or a desk that needs HDMI without active adapters. Newer Thunderbolt 4 docks are more flexible, but the SD2400T can still handle a straightforward dual-DisplayPort workstation.

Frequently Asked Questions

Does the Kensington SD2400T support dual 4K monitors?

Yes. Kensington rates the SD2400T for two 4K displays at 60Hz through its two DisplayPort 1.2 outputs when it is connected to a compatible Thunderbolt 3 laptop.

Will the Kensington SD2400T work with a USB-C laptop?

No. The SD2400T requires Thunderbolt 3 at the host laptop. A USB-C port with no Thunderbolt support is not enough.

How much laptop charging does the SD2400T provide?

The dock provides up to 85W of USB Power Delivery 3.0 to the connected laptop. It includes a 135W external power adapter.

Does the Kensington SD2400T have HDMI?

No. It has two DisplayPort 1.2 monitor outputs. Kensington says HDMI monitors need active DisplayPort-to-HDMI adapters or cables.

Can an Apple Silicon MacBook use two monitors with the SD2400T?

It depends on the Mac model. The SD2400T uses native Thunderbolt video, not DisplayLink, so it cannot exceed the external-display limit built into the Mac.