"The Tourbograph is the only Lange chronograph with the Double-Split to have a 3hz frequency."
Sorry for my confusion about the above. My reading of it was "of the ALS Chronos with the double split function, only the Tourbograph (and not the original DS) has the 3 Hz movement" when what I should have read was "the Tourbograph and the DS are the only two ALS Chronos at 3 Hz"
I have been reviewing a lot of business contracts recently, so probably parsed the sentence too finely!
Best,
Gary