Prices updated
He6, He8, He10 and He12 name WD/HGST's helium-sealed enterprise hard drive generations by capacity - 6TB, 8TB, 10TB, 12TB. We stock and document He10 and He12; He8 is real but too thin to carry its own page (2 listings), and He6 is not stocked at all. WD's current live site uses neither He10 nor He12's name for its equivalent current products, which is one of several things this page could not confirm from WD's own documentation - see below for exactly what we could and could not verify.
We set out to source this from WD/HGST's own documentation before writing it, and we are reporting exactly where that attempt succeeded and where it did not, rather than filling the gaps with what is widely repeated. WD's PDF document library (documents.westerndigital.com) returned nothing to a rendering-free fetch on any URL tried, including its own robots.txt and domain root - a pattern consistent with the domain blocking automated fetches rather than the documents not existing. The Wayback Machine and HGST's legacy site were both unreachable to the same tool. WD's current live product pages are JavaScript applications: the raw page loads, but the specification and body content that would name a generation loads client-side and was never present in what we could fetch. So: no capacity list, no model-number digit scheme and no rename statement for He6 through He12 could be confirmed from a WD source. Access log and exact URLs tried are in this page's edit history.
What we could confirm live on 2026-09-12: WD's current site sells a "12TB Ultrastar DC HC520" and has no page at all under a dedicated He-series URL (it 404s). WD's own footnote naming its current 550TB/yr-rated lineup lists HC680 down through HC310 plus Red Pro, Gold and Purple Pro - no He-series drive appears in it, and neither does HC510, the notional He10-equivalent name, whose own product page also 404s. We also read WD's own historical account of why the platform uses helium at all, which is attributed and quoted in the He12 FAQ rather than repeated here.
| Generation | Capacity | Status in our catalogue | Note |
|---|---|---|---|
| He6 | 6TB | Not stocked | No listing under any part number in our catalogue carries this generation - we hold nothing to price or decode. |
| He8 | 8TB | Excluded (below the listing floor) | 2 tracked ASINs, both HUH728080AL5200 - real, but below the 4-listing floor this cluster uses before a generation gets its own page. |
| He10 | 10TB | Built | 10 tracked ASINs across 6 part numbers - see the He10 page. |
| He12 | 12TB | Built | 14 tracked ASINs across 8 part numbers, and currently the dominant contributor to 12TB recertified supply - see the He12 page. |
Capacity-by-generation is not a WD-documented mapping we are citing - it is what our own catalogue directly shows for each generation name, which is a different and narrower claim. We use it here because it is verifiable against our own data and matches how every listing in each generation is actually named in the market this site tracks.
A part number like HUH721212ALE600 or HUH721010AL5204 breaks into a three-letter prefix, a six-digit field, then interface and format letters. The digit sequence right after the prefix is what this page and the He-generation pages match against - 7212 for He12, 7210 for He10 - because that is what the part numbers we actually hold demonstrate, not a formula WD publishes for the field generally. WD's own documentation does define the prefix (HUH marks the older He-branded generation, WUH the current DC HC naming) and the interface-suffix letters (which SAS or SATA interface, and 512e or 4Kn sector format) - that full, segment-by-segment decode lives on the part-number grammar page and on each part number's own decode page, and is not repeated here to avoid the two pages drifting out of sync with each other.
A level, not a change - the cheapest currently-buyable cost per terabyte in each generation we stock, whatever condition it comes in. This is the direct answer to whether the older, smaller-capacity generation is worth chasing over the newer one, computed from what is actually for sale right now rather than asserted from list price.
Right now He10 is the cheaper terabyte of the two - $23.50/TB against $27.50/TB for He12. That is not unusual for an older, smaller-capacity generation with a correspondingly smaller and more fully depreciated resale market, but it moves with whatever happens to be listed on any given day.
Neither figure is a discount or a change - both are plain daily observations of the cheapest listing in stock, and are labelled as levels for that reason. The generation pages linked above carry the new-versus-recertified CHANGE figures for each generation specifically, computed the matched way described in how we source and compute every figure on this site.
Two practical consequences follow directly from which generation a drive belongs to, and neither is about how fast it is. First, capacity ceiling: He10 tops out at 10TB and He12 at 12TB by definition, so a build that needs more usable space per bay than an older generation reaches is not a question price can answer - no discount makes a 10TB drive hold 12TB. Second, and less obvious, is depreciation and warranty exposure. An older generation has been out of first-line enterprise service for longer on average, which is part of why it reaches the secondary market at a lower price at all - but it also means any manufacturer warranty attached to a specific unit is more likely to have already lapsed by the time it is resold, regardless of what the generation name implies about the drive's design. Check the actual unit's coverage rather than assuming an older generation carries less warranty risk than a newer one just because it is older stock - the refurbished warranty guide covers what each tier of seller actually provides.
Sector format is the other cross-generation trap, and it is not tied to generation at all - both He10 and He12 ship SAS variants in 512e and 4Kn, under different part-number suffixes within the same generation. Buying "a He12" without checking the exact suffix is exactly the mistake the PN variant table on each generation page exists to prevent: two drives from the identical generation, identical capacity and identical interface can still refuse to join the same array over sector format alone.
Listed rather than silently omitted, because a reader searching "He6" or "He8" deserves to know we looked rather than assume we missed it.
It marks the drive as helium-sealed rather than air-filled, and the number after it names the capacity generation - He8, He10, He12 for 8TB, 10TB and 12TB. That naming survives in reseller listings, part-number databases and this site's own catalogue; it does not appear anywhere on WD's current live product site, which we checked directly rather than assuming (see the naming section below).
We could not verify a WD statement either way - see the naming section for exactly what we could and could not confirm. What is directly verifiable is that our own catalogue holds the identical part number, HUH721212ALE600, labelled both ways across different listings, and that WD's current site sells a 12TB product under the HC520 name with no equivalent He-series page.
By the digit sequence right after the three-letter prefix, matched against the part numbers each generation actually ships under - HUH7212xxxxxx and WUH7212xxxxxx are He12, HUH7210xxxxxx are He10. WD does not publish a documented rule for what those digits mean generally, which is why this page and the /part cluster decode by matching against real, held part numbers rather than by a formula. The full segment-by-segment decode, including what the letters after the digits mean, lives on the part-number grammar page linked below - this page does not duplicate it.
He6 is not stocked under any part number we track, so there is nothing to build a page from. He8 is real - HUH728080AL5200 - but only 2 tracked listings exist, below the 4-listing floor this cluster uses so a generation page is not mostly empty sections. Both would appear here the moment stock changes; nothing about the exclusion is permanent.