Loock S6ultra Smart Lock Review 2026: Triple Biometrics at ¥1,188

The Loock (Lockin) S6ultra is the ¥1,188-1,486 smart lock that answers the question Chinese buyers ask most in the 1,000-1,500 yuan tier: can a Xiaomi-ecosystem lock deliver palm-vein biometrics and a dual-camera cat-eye without paying Huawei or Kaadas flagship prices? On Pinduoduo’s 100-billion-subsidy program the S6ultra has hit ¥1,187.90 (a ¥1,303.90 price stacked with a 66-yuan store coupon and a 50-yuan platform subsidy, flagged by SMZDM on Aug 7 with a 100% positive vote and a category-ranking badge) and ¥1,303.90 in the Aug 11 restock; on JD self-operated the same S6 Ultra has been ¥1,394.36-1,485.54 with the national subsidy. The hardware: 3D face recognition plus palm-vein plus finger-vein unlocking (the triple-biometric combo Loock markets as “no blind spots”), a dual-camera cat-eye covering floor to ceiling with cloud playback, Mijia app integration with the rest of a Xiaomi smart home, and an auto-latching lock body. Xiaohongshu’s 409-like “S6 Ultra real-world test — is surveillance really dead-angle-free?” thread (official Loock account) and the 2,015-like “fingerprint locks are over, smart locks have entered the next phase” thread are the buy signals; the 20-like “S6 Max battery drain warning” thread, the 41-like “if you don’t want to die, never buy a Loock fingerprint lock” thread and the 27-like “Loock after-sales is genuinely terrible” thread are the recurring caveats; SMZDM’s community reports on firmware-update lockouts and after-sales disputes are the biggest controversies. Conclusion: ✅ Best value triple-biometric lock for Mijia-ecosystem households at the ¥1,188 deal price; ⚠️ skip if you have no stairs-free installation path (a 76-like thread warns against v6 Max on walk-up floors), if battery drain paranoia will keep you up, or if you need the after-sales safety net of a bigger brand.

Specifications

Specification	Detail
Model	Loock (Lockin) S6ultra
Biometrics	3D face + palm vein + finger vein
Cat-eye	Dual camera (floor-to-ceiling), cloud playback
Ecosystem	Mijia app + Xiaomi smart home integration
Lock body	Auto-latching, full-auto
Power	Battery-powered, low-battery alerts
Platform	Pinduoduo 100B subsidy / JD national subsidy
Price (2026-08)	¥1,188-1,486; all-time deal ¥1,187.90 on PDD

— the S6ultra in the finish SMZDM deal posts reference most often; the dual-camera array and the door-panel styling are the two details that dominate the discussion threads.

What Chinese Users Say

The triple-biometric buy signal & the category shift

The use case is the consistent praise point. The 409-like “S6 Ultra real-world test — is monitoring really dead-angle-free?” thread from Loock’s official account (Aug 2024) is the most-engaged test in the search; it demonstrates the palm-vein and dual-camera coverage that the “no blind spots” marketing claims. The 2,015-like “fingerprint locks are over, smart locks have entered the next phase” thread from Wei Zhi Xin (Sep 2024) — the single most-liked thread in the search — frames the category shift toward vein biometrics that the S6ultra rides. The 859-like “how to choose a smart lock for Double 11 — hands-on tested recommendations” thread (Da Shun Zi Zhai Zai Jia, Oct 2024) includes the S6ultra in its tested shortlist. The 79-like “Loock yyds!” thread (Yang Liu Jia Shi, Jan 2026) is the satisfied-owner version. SMZDM’s wiki roundup “in-depth teardown of 10 smart locks” (justfoyu) is the technical context. Key point: the S6ultra’s differentiator is the triple-biometric combo at a 1,000-1,500 yuan price — the category’s new “three-in-one” arms race that the 2,015-like thread says leaves fingerprint-only locks behind.

Battery drain & the walk-up-floor installation warning

The dark side is battery and installation. The 20-like “S6 MAX avoid — this terrifying battery drain speed” thread from IF (Nov 2024) is the flagship warning in the search; the 6-like “S6ultra abnormal battery drain, cannot be fixed” thread (OilMan, Apr 2026) extends it to the Ultra. The 76-like “v6 Max not recommended for buildings without elevators” thread (Zi Dong Hua, Nov 2025) is the installation warning — auto-latch locks drain batteries fast when residents repeatedly come and go through shared doors. SMZDM’s community article “Loock S30 Pro firmware update broke fingerprint unlock, B&B guests locked out” (post.awwex332) is the firmware-risk case. Key point: the triple biometrics and cat-eye are power-hungry — the S6ultra family’s battery reputation is the single biggest recurring negative, and the walk-up-floor warning applies to any full-auto lock that must cycle constantly.

After-sales, firmware and the “avoid Loock” cluster

The third theme is trust. The 27-like “Loock after-sales is genuinely terrible” thread (IF, Nov 2024), the 41-like “if you don’t want to die, never buy a Loock fingerprint lock” thread (Europa, Jul 2025), the 30-like “avoid Loock v5” thread (momo, Jun 2025), the 8-like “safety first, everyone avoid Loock” thread (Ayopoppy, Feb 2026) and the 2-like “went out to throw the trash and almost slept on the street” thread (Shou Mu Sui Sui Nian, Aug 2026) are the negative cluster. SMZDM’s “Loock smart locks have many failures, after-sales dodges responsibility, repair during warranty charged” article (post.a82r89oq) and “my rights-protection battle against JD Loock customer service” article (post.aqzp3o2k) are the detailed cases. Key point: Loock’s value pricing comes with a service reputation that Xiaohongshu threads and SMZDM community articles repeatedly flag — the 41-like “never buy” thread and the warranty-dispute article are the strongest warnings, so buy through a channel with its own return protection.

Pros & Cons

Pros

• ¥1,187.90 all-time deal on PDD 100B subsidy, 100% positive vote
• Triple biometrics: 3D face + palm vein + finger vein in one lock
• Dual-camera cat-eye with floor-to-ceiling coverage and cloud playback
• Mijia ecosystem integration with Xiaomi smart home
• Category-ranking badge on SMZDM, active deal flow (Aug 7 + Aug 11)
• Undercuts Huawei palm-vein flagship (¥2,578+) by more than half

Cons

• Battery drain is the top recurring complaint (S6 Max 20-like + Ultra 6-like threads)
• Walk-up-floor installations drain auto-latch batteries faster (76-like warning)
• After-sales reputation: 27-like “genuinely terrible” + warranty-dispute articles
• Firmware-update risk: S30 Pro lockout case in SMZDM community
• “Avoid Loock” cluster: 41-like + 30-like + 8-like negative threads
• PDD channel deal — returns depend on the subsidy platform, not a local store

vs Competitors

Lock	Price (2026-08)	Key difference
Loock S6ultra	¥1,188-1,486	Triple biometrics (face+palm+finger vein), dual cam, Mijia
Loock S6 Max	¥922-1,469	Finger-vein + 3D face, dual-cam screen, slightly cheaper
Loock v6 Max	¥2,993-3,025	Palm vein + face, right-open version, higher tier
Huawei Smart Lock 2 Ultra	¥2,578-2,888	AI palm vein + 3D face, HarmonyOS, IPX5
Kaadas P30 Pro Max	¥1,398-1,869	Dual-cam 3D face + radar active defense
Xiaomi M30 Pro	¥1,449-3,299	AI dual cam + palm vein, Mijia flagship
Dechambe Q50F Max	¥2,169-2,499	3D face + sentinel dual cat-eye

The S6ultra’s niche is the value tier of triple-biometric locks: at ¥1,188 it’s less than half the price of Huawei’s 2 Ultra and Xiaomi’s M30 Pro while offering the same biometric set (face + palm vein + finger vein) plus the dual-camera cat-eye. Against its own stablemate S6 Max, the Ultra adds palm vein on top of finger vein and face — the upgrade path for Mijia households. The trade-off vs the Kaadas P30 Pro Max is the security feature set (radar active-defense vs. triple biometrics); the trade-off vs Huawei is ecosystem (Mijia vs HarmonyOS) and service depth. At the ¥1,188 deal price, no other lock in the search offers this biometric stack.

FAQ

Q: Palm vein vs face recognition — do I need all three biometrics? A: Not strictly, but the combination is the point of the S6ultra: face for fast entry with hands full, palm vein for gloved or masked days, finger vein as the fallback when the camera is blocked. Xiaohongshu’s 2,015-like “fingerprint locks are over” thread captures why Chinese buyers are moving this way — fingerprint locks fail for wet/dirty hands and elderly users with worn prints, and vein reading solves exactly that. If you only want one biometric, the cheaper S6 Max (finger vein + face) saves ¥200-400, but you lose the palm-vein redundancy.

Q: Is the battery drain as bad as the threads say? A: The S6ultra family’s battery reputation is the biggest negative in the search — the 20-like “S6 MAX terrifying drain” thread and the 6-like “abnormal drain, can’t be fixed” thread document it. Real-world drain depends on traffic: a lock that cycles 30+ times a day (shared doors, frequent deliveries) will drain far faster than a quiet home lock. Loock’s low-battery alerts and the removable battery design mitigate it, but if you’re buying for a high-traffic door, budget for frequent charges and read the drain threads before committing.

Q: Is the ¥1,187.90 price real? A: Yes — it was a Pinduoduo 100-billion-subsidy deal on Aug 7, 2026 (¥1,303.90 price, 66-yuan store coupon + 50-yuan platform subsidy), flagged by SMZDM with a 100% positive vote and category-ranking badge; the same SKU re-appeared at ¥1,303.90 on Aug 11. JD’s national-subsidy path has been ¥1,394.36-1,485.54. The ¥1,188 requires catching the PDD subsidy window; ¥1,300-1,400 is the realistic everyday range.

Q: I live in a walk-up building — will this work for me? A: Read the 76-like “v6 Max not recommended for buildings without elevators” thread first. The warning isn’t S6ultra-specific — it’s about full-auto locks on shared walk-up doors, where constant cycling drains batteries and mechanical wear is higher. The S6ultra installs fine on a standard apartment door with an elevator; for walk-up buildings, factor in battery frequency and confirm your door type with the installer before ordering (installation is free with most deals).

Q: How does the dual-camera cat-eye compare to a dedicated video doorbell? A: The S6ultra’s dual camera is designed to cover floor to ceiling (no dead angle — the official 409-like test’s claim), which a single-camera doorbell can’t do: it sees packages at your feet and visitors’ faces at the same time, with cloud playback on the Mijia app. It’s not a full doorbell substitute (no two-way voice on every variant, check the spec), but for the price it removes the need for a separate camera above the lock. If you already run a Mijia doorbell, the marginal value is smaller.

Rating: 7.8/10

Who should buy this: Xiaomi-ecosystem households who want the triple-biometric stack (face + palm vein + finger vein) and a dual-camera cat-eye at a value price — the ¥1,188 PDD deal is the cheapest path to palm-vein unlocking in the entire search, beating Huawei by more than ¥1,000; also families with elderly members whose worn fingerprints fail on older locks, and buyers who like the “one app, whole home” Mijia setup. Who should skip: Walk-up-floor residents (battery and wear warnings from the 76-like thread), anyone who wants a strong after-sales safety net (the 27-like and 41-like service complaints plus the SMZDM warranty-dispute article are the loudest negatives), battery-anxious buyers who check charge levels daily, and premium-brand shoppers for whom Huawei’s HarmonyOS depth or Kaadas’s radar active-defense is the comfort pick.