Urwerk built its name on a watch with no hands. The UR-101 arrived in 1997 alongside the UR-102, its hours carried across a 180-degree arc by satellites, and the Green Mamba is that watch back on the bench: a black shell, an emerald minute track, and nothing else competing for your eye. It is the third UR-101 revival in two years, following the bronze T-Rex of 2025 and this spring’s gem-set Diamond Sky.
Felix Baumgartner and Martin Frei built the brand on that display. The 101 is now the canvas for Urwerk’s revivals, and this is the plainest one yet.
Urwerk UR-101 Green Mamba
41mm black PVD steel case · 48-hour power reserve · metallised sapphire crystal
Price: $39,830
Where to buy: More details at Urwerk
A satellite does the pointing
Two satellites ride a carousel, each carrying hour numerals. The satellite in play drags its numeral along the green arc from 0 to 60, and where that numeral sits on the arc gives you the minutes. Read the photo up top and the system explains itself: the 8 sits a third of the way across, so the watch is showing twenty past the hour. The carousel under them is snailed, a finish Urwerk specifies for the UR-101.
The hour and minute markers are painted with Super-LumiNova. Green does the daylight work. After dark, the lume takes over.
The 60 at the end of the arc is picked out in red, the one warm note on the dial. It is the handover point, where the satellite ends its run and the next hour starts its crossing.
The 1997 silhouette, kept
The case stays true to the original’s dome: 41mm across, 10.3mm thick, steel under a black PVD coat. A black PVD steel caseback closes the underside. The crystal is metallised sapphire with an anti-glare treatment, and the metallised layer is why the display window sits like a visor, dark at the edges and clear over the arc. Water resistance stops at 30 meters, which covers splashes and rain and not much beyond.
The dome is not symmetrical. It swells over the display window and drops away toward the lugs, a profile the 1997 original drew and every revival since has kept. From the side, it looks like a pebble with a visor cut into it.
The crown sits at 12 o’clock, where the UR-101 has always kept it. This shape predates the big satellite machines Urwerk is known for now, pieces like the UR-112 Aggregat we covered back in 2021, and next to them the 101 looks like the sketch the rest of the line grew out of.
A Vaucher base does the driving
Calibre UR-1.01V runs the display, an automatic movement built on a Vaucher base with Urwerk’s satellite module on top. It beats at 28,800 vibrations per hour and holds 48 hours of reserve off 28 jewels. Copper, brass, and ARCAP P40 appear in the component mix, a spread of metals chosen part by part rather than by habit. No thinness chase, no decoration for its own sake. The job is torque and timing for a carousel that never stops moving.
Finishing runs snailing, sandblasting, and satin brushing, with chamfered screw heads. None of it shows once the watch is together, because the caseback is solid steel with no window.
Setting runs through that crown at 12, a two-position piece. The flanks stay clean because of it.
One strap, no options list
The strap is black rubber with a black calfskin lining, closed by a pin buckle in black DLC-coated steel. One strap, one colorway. The rubber carries a woven texture, visible in Urwerk’s photographs, and the short, angular lugs pull it in tight against the case. At 41mm and a hair over a centimeter thick, the whole thing wears flatter than the dome suggests.
Price and availability
Urwerk prices the Green Mamba at CHF 33,000 before taxes, which converts to about $39,830 at today’s rate. Fifty pieces will be made, sold through Urwerk and its retail partners, and the release prints no on-sale date. Against its own siblings the number surprises: the bronze T-Rex listed at CHF 38,000 and the Diamond Sky at CHF 85,000, so the plainest of the three revivals is also the cheapest way into the UR-101 line.
At 10.3mm it splits the family on thickness too, slimmer than the 11.86mm T-Rex and thicker than the 9.33mm Diamond Sky, the middle of the three on the wrist as well.
Urwerk’s total output runs to roughly 150 watches a year across every line it makes. A 50-piece run of one reference is a third of that bench time, which tells you how seriously the brand takes its founding model.
| Model | Urwerk UR-101 Green Mamba |
|---|---|
| Case | Matte steel, black PVD coating |
| Dimensions | 41mm × 10.3mm |
| Caseback | Black PVD steel |
| Crystal | Metallised sapphire, anti-glare treatment |
| Water resistance | 30 meters (3 ATM) |
| Display | Wandering hours on two satellites, 180-degree minute scale |
| Markers | Super-LumiNova |
| Movement | Calibre UR-1.01V, automatic, Vaucher base |
| Jewels | 28 |
| Frequency | 28,800 vph (4 Hz) |
| Power reserve | 48 hours |
| Strap | Black rubber, black calfskin lining |
| Buckle | Black DLC-coated steel pin buckle |
| Edition | Limited to 50 pieces |
| Price | $39,830 |
Urwerk UR-101 Green Mamba
41mm black PVD steel case · 48-hour power reserve · metallised sapphire crystal
Price: $39,830
Where to buy: More details at Urwerk
Fifty pieces is a small room, and the Green Mamba fills it with the purest version of the original idea. No gem-setting, no bronze sculpture, no complication stacked on top of the one that built the brand. Just a black shell and a green arc, doing the job the 1997 watch was drawn to do. If the revivals continue, this is the one the others will be measured against.
