Sinn Spezialuhren 303 M-mph

The Sinn 303 M-mph, reference 303.042, is a chronograph in a polished 41 mm steel case. Beneath sapphire crystal, the matt black dial carries a model railway tachymeter scale in miles per hour. The 17 mm thick case has a see-through back and a screw-down crown, water resistant to 200 metres. The movement is self-winding calibre Valjoux 7750. The luminous hour indices surround the date and weekday displays alongside small seconds. Kilometre-per-hour and mile-per-hour scales appear in a table on the back.