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Home/Browse/Otsuka Lotec/5号改
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Otsuka Lotec 5号改
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Otsuka Lotec · 5号改

Otsuka Lotec 5号改

Stock unknown

Case

Diameter
40.5mm
Thickness
7.6mm
Lug width
22mm
Material
Stainless Steel
Water resistance
30m

Crystal & dial

Crystal
Sapphire

Movement

Caliber
Miyota 90S5
Type
Automatic
Power reserve
40h

Miyota

Miyota's open-heart variant of the 9015 platform, featuring a skeletonized dial-side plate that exposes the balance wheel through a cutout in the dial. Shares the same reliable 28,800 vph architecture and 42-hour power reserve as the standard 9015. Popular among microbrands offering open-heart designs at accessible price points without resorting to Chinese movements.

Design language

Case shape
round
Dial style
skeleton
Bezel
none
Bracelet
rubber_strap

AI-detected from the product image

Alternatives

01The market

Market prices.

RetailNot listed

The forum market

See what sellers are asking.

Active listings2Across watch forums
Closed · 90d1Asking-price history

Browse forum listings and their asking prices. Market+ adds medians with their sample sizes and the weekly trend.

02The connection engine

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03The community take

Owners talk.

“

Otsuka Lotec 5号改 is praised for its unique in-house satellite hour module with miniature ball bearings, built around a Miyota 90S5 automatic movement and a prominent box sapphire crystal. Its bezel-less design and 12.2mm thickness allow it to fit comfortably under cuffs, offering a unique complication at a price of around $4,500 or JPY 748,000, with availability limited to Japan via lottery. Some reviewers question if its overt complexity overshadows the mystique found in other Lotec models. Overall, owners and reviewers rate the Otsuka Lotec 5号改 highly for its avant-garde Japanese design and unique wandering hours complication.

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04The paper trail

In collections

Unique

Collection · 6 watches

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05The discussion

Talk about the Otsuka Lotec 5号改.