UtechSmart UCN3317-3: a two-plug MacBook hub with shared C roles review

A direct-fit hub needs a physical fit first

The UtechSmart UCN3317-3 plugs directly into two neighboring USB-C connections on a compatible MacBook. Its design suits a small side-mounted workspace with three USB-A peripherals, card access and an HDMI screen. Before considering speeds, confirm the exact computer and the space around those two connectors. UtechSmart specifically excludes use with MacBook Pro and Air laptop cases.

The maker names MacBook Pro models from 2016 through 2021 and MacBook Air models from 2018 through 2021. That is the retained physical-fit scope, not a promise about every later enclosure. A hub with fixed paired plugs is less forgiving of changed port spacing or a protective case than a cabled adapter.

Separate ordinary USB speed from Thunderbolt

The three USB-A3.0 outputs are rated for signalling up to 5Gbps. They serve ordinary accessories such as appropriate storage, input devices or a webcam. Their actual transfer performance depends on the peripherals and shared connection. Three sockets do not promise three simultaneous independent 5Gbps file transfers.

The multifunction USB-C socket is described as Thunderbolt 3 with transport up to 40Gbps. That rating does not establish a 20Gbps ordinary USB data output. The retained specification does not separately identify the ordinary USB data line rate for that socket, so this reference leaves it unknown. A Thunderbolt headline and a USB data requirement need different checks.

One multifunction socket means alternative arrangements

The same USB-C socket can handle data, a charging input or a compatible video connection. Those uses occupy one physical socket. With it connected to a PD charger, it is not also an available ordinary USB-C accessory port or a second independent monitor connection. Plan the arrangement around the role you actually need.

UtechSmart specifies charging pass-through up to 100W but does not establish a separate net notebook delivery figure here. A suitable source and the notebook's power negotiation determine the result. The package is not treated as including a 100W AC supply. For an HDMI desk that also needs charging, reserving this multifunction socket for power is the straightforward arrangement.

Intel dual displays and the explicit M1 exception

The HDMI output supports up to 4K at 30Hz. The product's technical table gives the Thunderbolt 3 USB-C output up to 4K60, while broader feature wording also mentions 5K. This reference uses the clear 4K60 technical-table mode and does not promote the conflicting 5K language into a guaranteed selection.

For a compatible Intel MacBook, UtechSmart says HDMI and the Thunderbolt 3 connection can operate simultaneously for mirror or extended displays. A uniform 4K30 arrangement respects the slower HDMI connection. The documentation explicitly says the 2020 M1 MacBook Pro and Air do not support dual display through this hub. That exception is retained, and later unnamed M-series chips are not inferred from the broad year range.

Using USB-C as the second video connection also occupies the multifunction socket. The source does not establish simultaneous charging through a separate socket in that arrangement. A comparison that combines dual screens, a spare C data output and a dedicated charging input would invent connections this hub does not have.

Cards and the practical choice

The SD and microSD readers support simultaneous use, with the maker listing up to 104MB/s and cards up to 2TB. Those are card-interface claims rather than measured transfer results for every card. The hub is approximately 4.96 ×1.18 ×0.4in and weighs 1.76oz, giving it a compact footprint next to a fitting computer.

Choose the UCN3317-3 for that specific direct-fit MacBook arrangement and its three ordinary USB-A connections. Decide in advance whether the multifunction socket will serve charging, data or a display. The product becomes much easier to assess when those roles and the explicit base-M1 screen limit remain visible.

For travel, protect the fixed paired plugs from sideways force and verify that the adapter can seat fully in the intended computer. The published fit restriction matters even when the underlying port protocol would otherwise be suitable.