Thunderbolt 5 (80Gb/s) PCIe and Connectivity Expansion Solution
Unlock Your Pro Potential
- Expands Small Machines: Use video capture, high-speed fiber/Ethernet, NVMe RAID, audio I/O, and other cards to unlock the potential of MacBooks, Mac Studio, Mac mini, and other space-constrained computers lacking a PCIe slot
- Internal Class Speed: Over 6000MB/s bandwidth available for simultaneous read/write
- Pro Level Card Ready: (1) PCIe 4.0 x4 (x16 mechanical slot) for half-length, full-height, single or double-width (including those with daughter board) cards
- Expanded Connectivity: Three Thunderbolt 5 (USB-C) 80Gb/s ports each with 15W power delivery for more device, display, and drive possibilities
Expand Your Capabilities Effortlessly
We get that you love your marvelously slender Mac or PC but also understand you often wish it offered more functionality. Now with the OWC Mercury Helios 5S, you can give your notebook, small form factor, or “all in one” desktop machine pro grade, full-size workstation capabilities. Whether you want to use an ultra-fast storage, 8K video capture, audio DSP, or high-speed networking PCIe card, Mercury Helios 5S makes it easy via a single Thunderbolt or USB4 connection and with no tools required. Plus, with three additional Thunderbolt 5 ports, it also gives you a handy next-gen connectivity hub. Embodying the heritage of innovation that has made OWC the global leader in Thunderbolt solutions, Mercury Helios 5S expands your capabilities effortlessly so you can think outside the traditional bulky desktop box when it comes to PCIe-based workflows.

Internal Class SpeedUp to 6000MB/s bandwidth available for simultaneous read/write |
Widely CompatibleUse with Thunderbolt 5/4, USB4 Macs and PCs, and Thunderbolt 3 Macs |
Expands Small MachinesUse video capture, high-speed fiber/Ethernet, NVMe RAID, audio I/O, and other cards to unlock the potential of MacBooks, Mac Studio, Mac mini, and other space-constrained computers lacking a PCIe slot |
Whisper QuietAircraft grade aluminum housing with high-efficiency, adjustable speed cooling fan provides cool, nearly silent operation |
Pro Level Card Ready(1) PCIe 4.0 x4 (x16 mechanical slot) for half-length, full-height, single or double-width (including those with daughter board) cards |
Easy Card InstallsCaptive thumb screws so no tools required |
Expanded ConnectivityThree Thunderbolt 5 (USB-C) 80Gb/s ports each with 15W power delivery for more device, display, and drive possibilities |
Complete, Secure, and ConvenientIncludes Thunderbolt 5 80Gb/s cable, power cord retainer, and auto power on/off with your computer |

Full-Speed PCIe Performance Ahead
Forget the belief that internal is always faster than external. The Mercury Helios 5S delivers up to 6000MB/s of bandwidth so you can run modern PCIe 4.0 cards at full speed while still accommodating data-hungry external Thunderbolt drives. Whether you're editing multi-cam 8K footage, running real-time audio processing, or transferring terabytes across a 25GbE network card, Mercury Helios 5S gives you the performance you'd expect from an internal PCIe slot with the flexibility of an external one.

Install Cards in Seconds
Ideal for creative professionals, post-production houses and VFX teams, IT personnel, and developers whose jobs demand easy-to-use, time-saving solutions, Mercury Helios 5S features a tool-free design. Compatible with half-length, full-height, single or double-width pro-level PCIe cards from leading brands like AJA, Apogee, ATTO, AudioScience, Avid Pro Tools, Blackmagic Design, Intel, RME Audio, Solid State Logic, Universal Audio, and OWC, you can use a wide range of pro-level options in seconds:
- Disconnect the Thunderbolt cable and power cord from Mercury Helios 5S
- Loosen the two captive thumb screws to install or swap a card. If your PCIe card is double-width or includes a daughterboard, the Helios 5S mesh panel is removable
- Reconnect the Thunderbolt cable and power cord to Mercury Helios 5S
Note: If your PCIe card requires a driver, always follow the manufacturer's instructions for installation

Triple Your Possibilities
With three Thunderbolt 5 (USB-C) ports, each capable of 80Gb/s throughput and 15W of power delivery, you can easily connect high-performance drives, 8K displays, or other peripherals. Whether you want to create a daisy chain of self-powered Thunderbolt devices or connect USB-C devices up to 80Gb/s, your connectivity options are unlimited with Helios 5S.

Ready for Today and Yesterday
Whether you’re pushing a Thunderbolt 5 machine to its max or still relying on a trusty Thunderbolt 3/4 Mac, Mercury Helios 5S offers plug-and-play expansion across Thunderbolt and USB4 generations. Your PCIe card is secured in an aircraft-grade aluminum chassis with a nearly silent high-efficiency fan so you and the Mercury Helios 5S stay cool under pressure.
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OWC Thunderbolt Cable IncludedOWC Mercury Helios 5S comes with a certified 0.7M OWC Thunderbolt 5 (USB-C) Cable. But if your workflow demands a different length to make the connection, OWC Thunderbolt 5 (USB-C) Cables are the perfect choice. |
Includes
- (1) OWC Mercury Helios 5S PCIe Expansion Solution
- (1) 0.7M (28") Thunderbolt 5 Cable
- (1) 90W External Power Supply
- (1) 1.8M (70.9") Australian Power Cable
- (1) Getting Started QR Insert Card
- (1) Support Manual for OWC Mercury Helios 5S (digital)
Expansion Slots
- (1) PCIe 4.0 x4 slot
Device Ports
- (1) Host Port - Thunderbolt 5 (USB-C) up to 80Gb/s
- (3) Thunderbolt 5 (USB-C) Ports
Display Support
- Up to three 8K displays @ 60Hz,
- or two 8K displays @ 120Hz
Housing Material
- Aluminum
Fans
- (1) cooling fan
- Adjustable speed internal switch
- The factory default fan setting is ‘Low’. Adjusting the fan speed to ‘High’ may be needed when using PCIe cards that generate a sizable amount of heat such as storage cards with multiple NVMe SSDs, dual 10GbE network interface cards, or enterprise grade RAID controllers.
Dimensions
- Height: 8.2 cm (3.2 in)
- Length: 23.3 cm (9.2 in)
- Width: 14.3 cm (5.6 in)
Weight
- 1.7 kg (3.75 lbs)
We are a registered New Zealand company (Upgradeable Limited), all orders include 15% GST. You are protected by local consumer law when you buy here. All product ships from our Australian warehouse until we can set up local distribution.
