The Bell & Ross BR 01, launched in 2005, is a square-cased watch inspired by aircraft cockpit instruments. The case is about 46 mm, with a round dial set in a square bezel held by four screws, and a very legible dial with large luminous numerals. It is a steel watch with an automatic movement, on a rubber or leather strap. I could not confirm full official specifications from a single source.

It was the brand’s first model and was designed around the idea of a pilot’s instrument that can be read at a glance, an approach that Bell & Ross extended into its BR 03 and BR 05 ranges. The BR 01 name later covered a chronograph version.

The community sees the BR 01 as the origin of the square aviation watch, though its large size divides opinion. The BR 01 line remains in production in newer versions.