Reference 2901.51.82 has a 42mm case with a black bezel inlay. The dial features orange numerals. It is fitted with a black rubber strap.
Reference IW3331-07 has a stainless steel case and a black carabou strap; it was also available with a brown caribou strap (IW3331-05) or with a black alligator strap (IW3331-06). The gold version carries the reference number 3331-03.
All of Sinn's watch designs adhere to the principle that ?form follows function?, and the U1000 is no exception, with an imposing appearance that underscores its robustness and functional reliability. These are indispensable characteristics for anyone with the highest expectations of suitability for everyday use for a personal safety system under extreme diving and usage conditions.