It’s that time again: Lange limited edition time! Around this time each month in 2019 (through October), A. Lange & Söhne will release a different limited edition watch to celebrate the 25th anniversary of the Lange 1. Each watch is rendered in white gold with a silver dial/blue hands and markers combo that is flat-out stunning. Today we’re getting the most extreme incarnation yet, a new rendition of the Lange 1 Tourbillon Perpetual Calendar. The basics of what you get are right there in the name, but this watch executes on that promise in some really unusual and compelling ways. First off, the tourbillon is totally hidden, only visible through the sapphire caseback, suspended between two curved bridges (engraved with a 25th anniversary motif in the case of this LE). Then there’s the QP, which doesn’t use a standard layout. Instead, Lange takes advantage of the Lange 1’s unique dial design, setting the months around the outer edge, placing the days of the week where you’d typically find the power reserve indicator, and placing the moonphase display in the lower portion of the running seconds register. This is a mega watch that doesn’t rub your nose in how mega it really is, and with just 25 examples being produced, it’s legitimately rare too.