Guides

Tritium watches carry sealed radioactive sources holding up to a gigabecquerel or more, and are sold under exemptions that are written down with numbers attached. The dose case for those exemptions is strong. The disclosure that comes with them is, in the United States, deliberately less than a smoke detector's — and most brands add nothing.

Silicon hairsprings are sold as an unambiguous upgrade and bought as one, by people on both sides of the counter who mostly cannot say what they change. The honest version, built from the patents and court filings rather than the marketing copy — what silicon actually fixes, what a widely repeated shock-resistance claim turns out to be about a different material entirely, and the serviceability question the industry is now quietly hedging against with metal alternatives of its own.

With premiums gone, the grey market is simply a cheaper way to buy the same watch, and the buying advice has not caught up. This is what protection a grey purchase actually carries in the UK — the statutory rights that apply identically at a grey dealer and an authorised one, the credit card protection that stops dead at a cash price of £30,000, and the platform guarantees that are commercial policy rather than law.

"Chronometer" is printed on three different kinds of test: an independent Swiss body that tests a bare movement to one published number, a government metrology institute whose own rulebook sets three different numbers and lets the brand run the test itself under audit, and a layer of in-house standards that are sometimes stricter than both and sometimes just a name. A working guide to what each one actually checks, from the standards themselves.

"Swiss made is not a description of where a watch was built. It is a test with five conditions, four of which are about process and one of which is a percentage — and the Federation of the Swiss Watch Industry publishes a worked example in which the same watch, with the same components at the same costs, comes out at 75% or 87% depending on which of two permitted methods the manufacturer picks. Both are legal. Neither is a secret. Almost nobody buying a watch has seen either."

Every brand publishes case diameter and almost none publish lug-to-lug, which is the measurement that actually decides whether a watch fits. A working guide to the numbers that govern fit, and how to take the one that counts yourself.

Deadbeat seconds explained — the mechanical complication that makes a fine watch tick like a cheap one, why it exists, and every watch that matters, from the Rolex Tru-Beat to the Habring² Erwin.