While Isotope hasn’t produced an event exclusive watch for British Watchmakers’ Day 2026, they are still unveiling a new watch at the show. It’s the Moonshot Chronograph Thunderclap, a vibrant reinterpretation of their signature chronograph that introduces the use of a telemeter scale for the first time. It’s a limited edition of 30 pieces and is available to be discovered from today for attendees of the British Watchmakers’ Day event, which also takes place today, March 7th.
First, what is a telemeter scale? It’s a type of chronograph scale that instead of being used to calculate speed as with a tachymeter, is used to calculate distance. It all comes down to everyone’s favourite high school equation: Speed = Distance/Time. A telemeter uses the chronograph function to time the difference between when you see an event occur and when you hear it to calculate how far away that event was when it happened. You are timing how long it takes something travelling at the speed of sound to reach you.
The most common example of a telemeter’s use, and the reason for this watch’s name, is to calculate how far away a storm is. When you see a flash of lightening, start the chronograph. Then, when you hear the thunderclap that follows, stop the chronograph. The telemeter will then tell you how far away the storm is. If you take multiple readings, you can discover if the storm is getting closer or further away and whether you should bring in the laundry from the line. Other applications include military scenarios where you want to estimate how far away that mortar explosion was from your position.
For the visuals of the watch, Isotope have teamed up with watch designer Matt Smith-Johnson, who goes by the moniker Teenage.Grandpa online. He’s known for a bold, modern style, which is where the use of ultraviolet and storm grey comes to the fore. The 41mm diameter x 15mm thickness case lets its sandblasted titanium do all the talking, paired with a dimple dial and telemeter scale in a slightly darker shade of grey that feels brooding and stormy. The purple finds a home across the markings of the telemeter scale, the chronograph pushers and the distinctive cover style chronograph subdials.
One of the more unusual aspects of the Moonshot Chronograph is that it’s offered with a choice of movements. Either the ETA Valjoux 7753 or the Swiss Landeron 73, both operating at a 4 Hz frequency with 44-hour power reserve. The watch is priced the same for both options, though what does affect the price is whether you opt for a titanium bracelet or purple FKM rubber strap. The strap option is priced at £2,400 while the bracelet is £2,720.
Price and Specs:
More details at Isotope Watches.
