U-Boat Capsoil Darkmoon Kama Quartz Watch with Green Dial.
The Capsoil collection fills the case completely with a low-viscosity oil, allowing the dial to be viewed through the fluid beneath a compensation bubble that accommodates thermal expansion between 0 and 60 °C. This Capsoil Darkmoon Kama features a 46.5 mm uncoated stainless steel case.
A Swiss Ronda 762 quartz movement operates while submerged in the oil, protected beneath a domed sapphire crystal. The crown screws down, while a Locking Ring System made of 316L stainless steel provides access to the battery without requiring factory intervention. The applied U-shaped hour marker is treated with Super-LumiNova, and the case back is laser-engraved with a QR code.
The brushed sunray metal dial has a green finish beneath the purple and black photochromic filter. The hands are treated with Super-LumiNova for legibility in low-light conditions. The watch is fitted with a calfskin leather strap secured by a 316L stainless steel buckle.
It fills the space between the dial and the crystal. Light travels through the oil at nearly the same speed as through the crystal, making reflections disappear and the hands appear to sit on the surface. An air bubble accommodates changes in oil volume as the temperature changes.
The design traces its origins to a drawing Ilvo Fontana made in 1942 for the Italian naval forces, a diving watch that remained on paper. His grandson, Italo Fontana, revived the design in Lucca and founded U-Boat around its proportions and distinctive left-side crown.
The layer over the dial darkens when exposed to ultraviolet light and becomes clear again indoors, using the same chemistry as photochromic eyeglass lenses. As a result, the dial has a different appearance outdoors than it does at a desk.
It is a large watch. Compare the 46.5 mm diameter with a watch you already own before ordering, because the diameter determines the fit and is the measurement that photographs flatten. A loose cuff will fit over it.
Super-LumiNova is a phosphorescent pigment charged by exposure to daylight or artificial light. It provides its brightest illumination during the first few minutes and gradually fades over the following hours. Exposure to light recharges it for subsequent use.
Yes, we are an Official U-Boat Authorized Dealer, and an authorized dealer for every brand we carry.
With over 15 years in the luxury market, we guarantee the authenticity and quality of every piece we sell.
Your order arrives brand new in its original U-Boat packaging, with all official documentation and the U-Boat warranty card, stamped and dated by us.
The warranty covers manufacturing defects. It doesn't cover normal wear and tear or accidental damage — and on watches, it doesn't cover straps, bracelets, or batteries.
Questions about a specific piece? Our specialists are happy to help.
You'll find availability on every product page, right above the Add to Cart button. Here's what each status means:
"In stock, ships within 24 hours" or "Only X units left" — the item is in our warehouse and ships the next business day after you order.
"In stock, ships within X days" — the item is held at our secondary warehouse. We allow a few days to inspect and authenticate it before it ships.
"Check delivery date" — the item is available to order, but we confirm the exact date with the brand. As soon as you order, we contact the manufacturer and email you an estimated delivery date.
Need something by a specific date? Tell us and we'll check before you buy. [Contact our team →]
Yes — free DHL Express shipping on all US orders of $250 or more.
Every order ships with a tracking number, so you can follow your package every step of the way. Shipments are fully insured and delivered by DHL Express with signature required.
Most in-stock orders arrive within 2–3 business days, depending on your location.
No, the price you see at checkout is the price you pay — nothing else.
The price you pay at checkout is the final price of the item delivered to your address.
DHL will never ask you for a payment on delivery, and no surprise invoice arrives afterward.
No handling charges, no processing fees, nothing added at the door.
We accept all major credit and debit cards, Apple Pay, Google Pay, PayPal, and bank wire transfer.
Every transaction is fully encrypted, and we never store your card details.
Financing. Choose PayPal at checkout and you may be offered the option to split your purchase into payments or finance it over time, including interest-free plans on qualifying orders. You'll see exactly what's available for your order before you confirm — plans, terms, and eligibility are set by PayPal and subject to their approval, with no obligation to take it.
Paying by wire, or buying more than one piece? [Contact our team →] and we'll take care of you personally.
You have 30 days from delivery to return your order.
How returns work. Just let us know and we'll email you a prepaid DHL Express return label — you never have to arrange a shipment or pay anything up front. The return shipping cost is deducted from your refund. If the item arrived damaged or wasn't what you ordered, the return is on us.
Your refund options.
To qualify for a full refund, the item must:
Not sure whether something qualifies? Ask us before you ship it back — we'll tell you straight. Contact our team.
Our specialists are here before and after you buy — no pressure, no obligation. Authorized dealer, official warranty, and guaranteed authenticity on every piece.