DSTB (Dial Side True Beat)

Watch the seconds hand step, and watch the mechanism drive it

A true-beat seconds hand advances in discrete one-second jumps and holds still between them, unlike the six-to-eight steps a second of an ordinary mechanical watch. On the DSTB the mechanism producing that behaviour is visible on the dial side, so the hand's motion and its cause can be observed together. A stepping hand with no visible mechanism driving it — or a quartz movement, which also steps once a second — is the substitution to watch for, and the exposed mechanism is what distinguishes them.

Dial-side architecture is self-evidencing

Where the movement is on the front of the watch, the dial is not concealing anything and cannot be used to disguise a substituted caliber. Compare the visible architecture directly against the published caliber. This is the strongest position an examiner can be in and it is worth recognising when a brand offers it.