Brand Seiko Caliber Number 5740C Base Caliber 5740 Movement Type Manual wind, mechanical Jewels 23 Vibrations Per Hour 36,000 bph.
Contents.OverviewThe 6R15 family was introduced in as a higher-spec derivative of the familiar. It was intended to replace the expensive 'high beat' -derived in mainstream watches, allowing that family to be used exclusively in more expensive models.The 6R is an movement which adds and to the existing 7S26 base. This is the main difference between the movements: The winding works now include two separate pinions on the bottom plate to add hand winding. It also features a hacking mechanism and pinned balance spring for adjustability. Thanks to a 510 mainspring, the 6R15 boasts 50 hour power reserve, and the faster-beating 6R2x series has a 45 hour power reserve.The 6R20 differs from the base 6R15 in many ways.
It beats at 28,800 vph and features a power reserve indicator and both day and date in a window.