Welcome to the world of fine luxury timepieces. In order to familiarize yourself with various watch brands and its functionality, its important for you to know some of the standard terms in the industry. Here are some commonly used terms.

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Flyback Hand
A seconds hand on a chronograph that can be used to time laps or to determine finishing times for several competitors in a race. Start the chronograph, putting both the flyback hand and the regular chronograph seconds hand in motion. 

To record a lap time or finishing time, stop the flyback hand. After recording the time, push a button and the hand will "fly back" to catch up with the constantly moving elapsed-time hand. Repeat the process to record as many lap times or finishing times as needed.See also: Rattrapante
Fold Over Clasp
The Fold Over Clasp collapses on itself and locks via a pressure tab. The clasp typically has several micro adjustment holes (as seen in the image) that can be used to adjust the bracelet size by non-jewelers. In time, the pressure tab often wears out and the clasp no longer stays closed. This has led to the following three different improvements on the Fold Over concept.See also: Fold Over Clasp with Push Button, Fold Over Clasp with Safety and Push Button or Double Locking Fold-Over Clasp
Fold Over Clasp with Push Button
This is the second of three improvements on the Fold Over Clasp. The Fold Over Clasp with Push Button Clasp provides a secure lock on a post that can only be released by pushing the two buttons. This improvement is more secure than the Fold Over Safety Clasp.See also: Fold Over Clasp, Fold Over Clasp with Safety, Fold Over Clasp with Safety and Push Button or Double Locking Fold-Over Clasp
Fold Over Clasp with Safety
This is the first of three improvements on the Fold Over Clasp. The Fold Over Safety Clasp provides a flap that folds over the closed end of the clasp which makes the clasp more difficult to open unintentionally.See also: Fold Over Clasp with Push Button, Fold Over Clasp with Safety and Push Button or Double Locking Fold-Over Clasp
Fold Over Clasp with Safety and Push Button or Double Locking Fold-Over Clasp
This is the third of three improvements on the Fold Over Clasp. This clasp combines the flap of the safety clasp with a push button lock to provide the wearer the maximum security available for any Fold Over Clasp.See also: Fold Over Clasp, Fold Over Clasp with Push Button, Fold Over Clasp with Safety