The Hanhart MAD Preventor HD12 takes the brand’s hardened case down to 36 mm for the first time, on a matte Black Forest green dial. It was developed with the British collector Russell, who posts as the MAD Watch Collector, and it is limited to 200 pieces from EUR 1,140. Hanhart quotes up to 1,200 Vickers for the case, a number that lands the watch in the middle of an argument German brands have been having for the better part of twenty years.
Press release with commentary in italics.
Commentary
The usual story about German hardened steel starts with Sinn. Konrad Damasko set up on his own in 1994 and spent the best part of a decade making hardened cases for Sinn, an arrangement that ended in 2002. Tegiment came the year after that, in-house, in the 756. Sinn now quotes 1,200 Vickers for tegimented stainless against roughly 220 for ordinary 316L, and German submarine steel took that to 1,500 in 2005. Damasko had already gone elsewhere, forcing nitrogen through a martensitic alloy to get a case that is hard the whole way down, 700 to 800 HV, with no soft middle to it.
Damasko’s reason for doing it that way is a standing criticism of everybody else: harden the surface alone and you get what the company calls an egg-shell effect. HD12 sits on the other side of that. Carbon is diffused into the steel to build a hardened zone that grades down into a softer core, with a transparent PVD layer over the top, for a quoted figure of up to 1,200 HV. The gradient is the part the company keeps pointing at, because it is what stops the case going brittle, and as a reply to Damasko it holds up.
Vickers, though, measures how a surface resists a diamond point pushed into it. That covers keys, doorframes and the edge of a desk. It covers a hard knock much less well. Hardness and toughness are different properties and they trade against each other. A case that shrugs off scratches can still take a dent, and on a hardened case that is the worse outcome, because the skin has nowhere to go when the core deforms under it.
None of which is an argument against the watch. Almost all the damage a watch takes is scratching, and scratching is exactly what HD12 is for. Add 15 ATM, a screwed back and a screw-down crown and the thing is properly thought through, at a price that isn’t silly. What 1,200 HV buys you is a case that still looks new after two years of ordinary wear, and that is worth paying for.
Release Details
Hanhart has expanded the Preventor HD12 line with a smaller case, developed alongside Russell, the British enthusiast who posts as the MAD Watch Collector. The Hanhart MAD Preventor HD12 is the first version of the model to appear at 36 mm and the first to wear a Black Forest green dial, and it is limited to 200 pieces.
The size is the headline here. Hanhart says it has been asked for a smaller Preventor repeatedly over the past few years, and at 36 mm the design carries noticeably more classical proportions than the 39 mm original does. Height is 10.50 mm, lug-to-lug is 43 mm, and by current standards that is a genuinely compact watch.
The more interesting decision is the lug width. At Russell’s suggestion, the 20 mm spacing was carried over unchanged from the larger model, and it has two consequences. The watch keeps a certain visual weight on the wrist, which a scaled-down 18 mm would have taken away, and the owner inherits the whole 20 mm strap market, which is a great deal larger than the 18 mm one. It is the kind of detail a wearer notices and a designer often does not.
The case is Hanhart’s HD12 steel, finished in a mix of satin and polished surfaces. Getting both out of a hardened case is not trivial, which is part of why the treatment runs in two stages. First a surface-hardening step diffuses a large quantity of carbon into the stainless steel, producing a gradual transition from a hard exterior down to a softer core. A transparent PVD hard coating then goes over the top. Hanhart states up to 1,200 HV as the result, against roughly 220 HV for conventional 316L, with corrosion resistance left intact.
Around it sit a smooth bezel, a screwed case back numbered sequentially out of 200, and a polished screw-down crown carrying the historic Hanhart ‘h’. The crystal is domed sapphire, anti-reflective on the inside face only, and water resistance is 15 bar, tested to DIN 8310.
The dial is matte green, named for the Black Forest region Hanhart has called home for decades, and it carries the historic Hanhart logo. Numerals, cathedral hands and the seconds hand are coated in Super-LumiNova C3 X2 GL. Hanhart makes a good deal of the legibility. A matte ground with strong contrast between dial, numerals and hands is more useful in daily wear than a lot of what gets offered at this money, so the emphasis is fair.
Inside is the Sellita SW200-1 in its true three-hand form, with no date and therefore only two crown positions. It runs at 28,800 vibrations per hour on 26 jewels, hacks, and holds at least 38 hours. Nobody buys this movement for glamour. It gets specified because it works and because any competent watchmaker can service it.
What Hanhart does with it is more distinctive. Every movement is tested and regulated at the manufacture in Gütenbach against an in-house standard: averaged across six positions, the daily rate must fall between 0 and plus 8 seconds, with no more than ten seconds of variation between individual positions. That is an eight-second window, tighter than the ten seconds COSC allows at minus 4 to plus 6, and it has been shifted deliberately so that the watch is never permitted to run slow in the main positions. This is a self-declared specification and not a third-party certification, which is worth saying plainly, though the thinking behind it is sound enough. A watch that gains is a watch you are never late by.
There are two strap options. The first is a calfskin band with an Alcantara lining, offered in black, dark brown or light brown on a pin buckle, and in three lengths. The second is a stainless steel bracelet given the same transparent PVD hardening as the case, with quick-release spring bars and a folding clasp with tool-free fine adjustment. That last feature matters more than the spec sheet suggests, because wrists swell over the course of a day, and being able to correct for it without hunting for a tool is often what decides whether a bracelet stays on the watch.
Pricing is EUR 1,140 on the calfskin strap and EUR 1,340 on the steel bracelet, both including 19% VAT. For context, the original 39 mm Preventor HD12 launched in September 2024 at EUR 995 and EUR 1,195, so the smaller watch costs more than the larger one did, with two years and a 200-piece limitation sitting between the two. Deliveries are expected from approximately the end of October 2026.
Where it sits against the obvious alternatives is less uniform than you might expect. Sinn and Damasko are the two German names most associated with hardened cases. Against Sinn the gap is wide, because the entry-level 556 is not tegimented at all and the cheapest tegimented model, the 836, is EUR 1,990. Against Damasko there is almost no gap at all: the DS30 starts at EUR 1,210, fractionally above the Hanhart on its strap and below it on the bracelet. So the Preventor HD12 undercuts the tegimented Sinns comfortably and lines up almost exactly with Damasko’s entry point. Whether it feels the equal of either in the metal is a separate question, and one that needs wrist time to answer.
The collaboration deserves a paragraph of its own. Enthusiast partnerships have become common enough that many of them amount to a name on a case back and a sold-out drop. This one is more modest and more useful. The 20 mm lug width came from Russell directly, and along with the 36 mm case it is one of the two decisions that determine how the watch actually wears. Hanhart has kept its own design language intact throughout. Nothing here reads as a departure from what the Preventor already was; it reads as the version a particular enthusiast wanted, built properly.
Hanhart was founded in 1882 by the Swiss watchmaker Johann A. Hanhart, in Diessenhofen, and moved across the border to Schwenningen in Germany in 1902. Today its mechanical watches are developed, produced and distributed from Gütenbach in the Black Forest. The company built its reputation on wrist chronographs and stopwatches, and it holds a significant place in the history of German watchmaking. Its stated priorities have stayed consistent: precision and reliability, legibility, simple and secure operation, and longevity.
Hanhart MAD Preventor HD12 Specifications
Model: Hanhart MAD Preventor HD12, in collaboration with the MAD Watch Collector
Reference: 792L.874-6429-1 (steel bracelet version)
Limited edition: 200 pieces
Movement: Sellita SW200-1, automatic, true three-hand with no date and two crown positions
Functions: Hours, minutes, central seconds; hacking seconds
Frequency: 28,800 vph (4 Hz)
Jewels: 26
Power reserve: At least 38 hours
Rate accuracy: Hanhart regulation, 0 to plus 8 seconds per day averaged across six positions; maximum ten seconds deviation between positions
Case: Satin-finished and polished hardened HD12 steel, up to 1,200 HV; smooth bezel; screwed case back with sequential limitation number out of 200; polished screw-down crown with historic Hanhart ‘h’
Measurements: 36 mm diameter, 10.50 mm height, 43 mm lug-to-lug, 20 mm lug width
Crystal: Domed sapphire with internal anti-reflective coating
Dial: Matte Black Forest green with historic Hanhart logo
Hands and numerals: Super-LumiNova C3 X2 GL coated numerals, cathedral hands and seconds hand
Strap: Calfskin with Alcantara lining in black, dark brown or light brown with pin buckle, in three lengths (S, M, L); or stainless steel bracelet with transparent PVD hardening, quick-release spring bars and folding clasp with historic logo and tool-free fine adjustment
Water resistance: 15 bar / 15 ATM per DIN 8310
Price: EUR 1,140 on calfskin, EUR 1,340 on the steel bracelet, incl. 19% VAT
Availability: Deliveries from approximately end of October 2026
Readers may also want to revisit our earlier look at the Hanhart Preventor HD12 in its original 39 mm form, and the Hanhart Preventor9 S Limited Production.
