Fledging Shell Thunder-Thunderbolt 3 SSD external storage

I was supplied a Fledging Shell Thunder-Thunderbolt 3 SSD Enclosure with a 1TB NVMe M.2 2280 SSD already installed, by Fledging’s Brand Manager for review.

Included with the unit is a Philips head screwdriver, a spare M.2 screw, an Installation Guide, and a (nifty 😊) Fledging sticker.

The unit weighs 4.4 oz (with the SSD installed), measures 3.77” x 2.62” x 0.58”.  It is nicely finished and feels very sturdy.  On one side of the case there are 3 small slots for the built-in fan to draw air, and 24 smaller slots on the opposite side for the exhaust of the heated air (as it blows across the M.2 SSD).  On the underside are four Philips head screws (one at each corner) to allow access to the enclosure.  Inside the enclosure is a small fan, and the board for inserting the M.2 2280 SSD, and a thermal cooling pad on the cover opposite the location of the SSD.  This unit came with a 1TB Phison M.2 2280 TLC SSD (PS5012-E12-27) and what appears to be a Kingston NAND Flash chip.

The following is from the Fledging website[1]:

  • Can be purchased as just the case, or with NVMe SSD 256GB, 512GB, 1TB and 2TB drives installed
  • MSRP with 1 TB US$299.99
  • Both macOS and Windows compatible
  • Has active cooling via a temperature sensing 4000 rpm fan
  • designed for 2280 and 2260 m.2 NVME and ACHI SSDs, not m.2 SATA SSDs, Apple OEM SSDs nor apparently Samsung EVO 970 Plus.  The manufacturer recommends Western Digital Black SN750 NVMe SSDs (without the heat sink)
  • Thunder only works for true TB3 ports and will not cross-function with a USB-C port.

Initial Set-Up

To start I formatted the Phison SSD using Windows format.  I ran both dynamic benchmarking and ‘field’ tests of the unit.

Benchmarking results:

I used a LG Gram laptop Z990 with an 8th Gen Intel® Core™ i7 processor and DDR4 dual-channel memory, 256GB M.2 2280 SSD,  16GB DDR4, Windows 10, and connected to its native USB-C 3.1 Thunderbolt™ 3 port with the Thunderbolt 3 cable supplied by Fledging.

Using Windows ‘winsat’

The native M.2 SSD LG Laptop results:

Sequential (MB/s) Read 508.84  Write 495.76

Random (MB/s) Read 325.24

The SanDisk 128GB Extreme microSDXC UHS-I V30 in LG Laptop results:

          Sequential (MB/s) Read 56.50  Write 52.76

Random (MB/s) Read 11.99

The Fledging Shell Thunder results:

Sequential (MB/s) Read 2559.95  Write 47.66

Random (MB/s) Read 1379.20

OWC Envoy Pro EX  USB-C 2TB SSD M.2 drivef[2]

Sequential (MB/s) Read 830.84  Write 885.88

Random (MB/s) Read 497.64

Using ATTO Disk Benchmark 4.01.0f1

The native SSD Laptop results at 256KB I/O data:

Sequential (MB/s) Read 518.74 Write 490.87 

The SanDisk 128GB Extreme microSDXC results at 256KB I/O data:

          Sequential (MB/s) Read 76.09  Write 69.22

The Fledging Shell Thunder results at 256KB I/O data:

Sequential (MB/s) Read 2.35  Write 465.45

Using AS SSD Benchmark 2.07316.34247

The native M.2 SSD LG Laptop results:

Sequential (MB/s) Read 504.39  Write 450.86

The SanDisk 128GB Extreme microSDXC results at 256KB I/O data:

          Sequential (MB/s) Read 83.70  Write 69.84

The Fledging Shell Thunder results at 256KB I/O data:

Sequential (MB/s) Read 1951.76  Write 929.92

OWC Envoy Pro EX  USB-C 2TB SSD M.2 drive

Sequential (MB/s) Read 918.79  Write 920.40

Initial Field Test

After benchmarking, the next step was to see how the Fledging Shell Thunder-Thunderbolt 3 did with real data.

I again used a LG Gram laptop Z990 with an 8th Gen Intel® Core™ i7 processor and DDR4 dual-channel memory, 256GB M.2 2280 SSD,  16GB DDR4, Windows 10, and connected to its USB-C 3.1 Thunderbolt™ 3 port with the Thunderbolt 3 cable supplied.

The first transfer was of 21.2GB (1,414 items including videos, images, pdfs and text files) to the Fledging Shell Thunder-Thunderbolt 3.    The transfer took 01:23.85 minutes to complete.  Accessing any of the transferred files, images, videos, and pdfs was instantaneous.   The case showed a thermal increase of 0.5⁰F (using a Raytek MT6 infrared thermometer)

For comparison, the identical 21.2GBs was sent using the same laptop to a OWC Envoy Pro EX. The transfer took 01:34.51 minutes to complete.  Accessing any of the transferred files, images, videos, and pdfs was instantaneous.   The case showed a thermal increase of 4⁰F (using a Raytek MT6 infrared thermometer)

Next, I transferred 72.8GB (8,972 items including videos, images, pdfs and text files) to the Fledging Shell Thunder.  Transfer took 08:49.19 minutes to complete.  Accessing any of the transferred files, images, videos, and pdfs was instantaneous.   The case showed a thermal increase of 9.0⁰F (using a Raytek MT6 infrared thermometer)

For comparison, the identical 72.8GB was transferred to the OWC Envoy Pro EX.  Transfer took 06:22.20 minutes to complete.  Accessing any of the transferred files, images, videos, and pdfs was instantaneous.   The case showed a thermal increase of 8.5⁰F (using a Raytek MT6 infrared thermometer).

Preliminary conclusions:

This Fledging Shell Thunder-Thunderbolt 3 SSD Enclosure is a very portable and relatively fast solution for Thunderbolt 3 users.  It is powered from the Thunderbolt 3 cable and remains very cool under normal use.  The fan is so quite that the only way I knew it was working was to feel the very slight breeze at the case (or by removing the case back and viewing the fan directly).

Its speed results in reading and writing data was a mixed bag: Its Read of the Windows speed test data was 3 times faster than the next best time of the other drives, but its Write was the slowest of all and a whopping 18 times slower than the best.

The results using the ATTO Disk Benchmark were equally surprising, in that the Fledging Shell Thunder-Thunderbolt 3 performed very poorly in the Read component, at almost a multiple of 220 slower than the best, while its Write performance was almost on par with the best.

The read results were so surprising that I reran the test and got similar results.  The only thing I can conclude is that the extreme differences between the two sets of results must be related to the algorithms used by Windows vs ATTO.

A third benchmarking tool, AS SSD Benchmark was used where the Fledging Shell Thunder was the fastest Read at nearly twice that of the OWC Envoy Pro EX, and very slightly faster in Write than the OWC Envoy Pro EX.

Of course, none of us really use a hard drive to run only standardized benchmarking tools (at least, most of us don’t 😊 ).  We use them for storing and retrieving data.

Here the Fledging Shell Thunder-Thunderbolt 3 fared better when compared in a somewhat Apples to Apples comparison with the OWC Envoy Pro EX.  In the 21.2GB mixed data file writing, the Fledging Shell Thunder was about 12 seconds faster, with no noticeable difference in the instantaneousness of the reading of the same file.  It also remained cooler.

With the large 72.8GB mixed data file, the Fledging Shell Thunder-Thunderbolt 3 was slower by about 2 minutes and 20 seconds compared to the OWC Envoy Pro EX in writing, and had nearly the same temperature increase during the write.  Again, no noticeable difference in the instantaneousness of the reading of the same file.

In summary, the Fledging Shell Thunder-Thunderbolt 3 SSD Enclosure offers a compact highly portable external drive for those who have a true Thunderbolt 3 port.  Note: this unit will not work with non-Thunderbolt 3 ports even though it fits, for example, a USB 3 port.  It has a built-in temperature sensitive very quiet fan.  You can purchase the enclosure without any M.2 SSD for about US$140 and put your own NVMe M.2 2280 SSD in or buy it with up to 2TB NVMe M.2 2280 SSD from Fledging.

Its read/write performance varied depending on the size of the data sets. The fact that it incorporates a fan means that it is not dust or water resistant (as the OWC Envoy Pro EX is).  So, depending on what your intended use is for an external drive and whether you have a true Thunderbolt 3 port, will determine whether this is the drive for you.

Oh, almost forgot: despite its name Fledging Shell Thunder-Thunderbolt, the unit makes absolutely no noise. 🙂

Overall Preliminary rating: 4 out of 5 abacuses


[1] https://fledging.net/products/shell-thunder

[2] See https://insight.daumphotography.com/2020/10/04/owc-envoy-pro-ex-with-usb-c-2tb-ssd-m-2-drive-ultra-portable-and-fast/