Grand Seiko

Grand Seiko 9RA2 Spring Drive power reserve: 120 hours

The Grand Seiko 9RA2 Spring Drive is an automatic movement that runs for about 120 hours (about 5 days) from full.

Found in

Grand Seiko Evolution 9 SLGA

Keeping it running

• On an average day an automatic gains roughly 4 hours of reserve per hour on the wrist, so about 30 hours of wear fills the Grand Seiko 9RA2 Spring Drive. Desk days charge more slowly.
• Most automatics can also be wound by the crown. If yours has stopped, a few dozen turns gets it going before you put it on.
• Off the wrist it stops about 120 hours after it was last full.
• If it does stop, don't set the date between 9pm and 3am. Here's why.

Never let it stop

Watch Winder counts down the reserve of every watch you own and reminds you before one stops. It already knows the Grand Seiko 9RA2 Spring Drive: type your watch's name and the reserve fills itself in.

Manufacturer's published figure. Real reserve varies with the watch's age and service; check your manual.