SW510 M BH b

Manual winding - chronograph Cam operated chronograph - two push-buttons Hours, minutes and small second at 9 o'clock 60 seconds chronograph in the center 30 minutes counter at 3 o'clock Optional: 15 minutes counter at 3 o'clock (SW511 M BH b) Manual winding Stop second device 28'800 vibrations per hour (4 Hz) 23 jewels Typical power reserve : 63 hour