Seiko NH70A
Factory specs
- Caliber
- NH70A
- Made in
- Japan or Malaysia
- Frequency
- 21,600 bph (3 Hz)
- Power reserve
- 41 h
- Jewels
- 24
- Hacking
- Yes
- Hand winding
- Yes
- Accuracy
- -20 / +40 s/day
- Diameter
- 27.4 mm
- Height
- 5.32 mm
- Functions
- Hours, Minutes, Seconds, Skeleton
- Equivalent to
- Seiko NH71A
- Same family
- Seiko 4R36, Seiko NH35A, Seiko NH36A, Seiko NH37A, Seiko NH38A, Seiko NH39A, Seiko NH71A, Seiko NH72A
Skeletonised no-date three-hander with nickel-plated parts; TMI lists it with the gilt NH71A in its "Skeleton Mechanical NH7" range, and Caliber Corner describes it as built on the NH35 (NH3) framework, hence the Seiko NH3x family. TMI spec sheet (rev. 16.11.2022): 12 lignes, Ø27.40mm, 5.32mm high, "Three Hands (skeleton)", 24 jewels, 21,600 vph, duration "more than 41 hours", accuracy -20 to +40 s/day (23 ±2 °C), manual winding, ball-bearing automatic winding in both directions, second-hand stop mechanism (hacking), antimagnetic ≥4,800 A/m, "non-corresponding with diver's watch" casing. TMI product page: Côtes de Genève decorated rotor, silver finish, country of origin "Japan or Malaysia". The NH71A (data/movements/seiko-nh71.yaml) is the same caliber with gold-plated (gilt) parts. Caliber Corner notes the Seiko-only 4R71 is the in-house equivalent with 23 jewels.
Watches with the Seiko NH70A
| Watch | Price from | Movement | Dia. mm | Thick mm | Crystal | Micro-adjust |
|---|---|---|---|---|---|---|
 Cadisen C8183 |
$140 | Seiko NH70A | 42 | 12.5 | Sapphire | — |
 Islander Baiting Hollow Steel Skeleton |
$329 | Seiko NH70A | 42 | 14.3 | Sapphire | — |
 Undone GAMEON Ultimate Shooter |
$410 | Seiko NH70A | 42 | 13.2 | Mineral | no bracelet |
 Undone Aquadeep K9 Crystal (NH70) |
$1,150 | Seiko NH70A | 43 | — | Sapphire | no bracelet |