Aristo 58mm Split Second Step Watch Timer with 10 Minute Register in Original Box

A really mint condition and fine example of a split second timer with 10 minute register. With the remarkable condition, I question it was ever really used.

Details:
MAKE
Manufacturer: Aristo
Country: Switzerland
Type: Open Face
Circa Date: 1960s
CASE
Size: 58mm.
Style: Open Face.
Material: Base Metal.
Decorations:  Plain.
Conditions:  C  2  (The case is in Perfect condition)
DIAL
Color: White.
Type: Porcelain.
Numerals: Arabic Numerals.
Hands: Baton Hands.
Conditions:  D  2  (The dial is in Perfect condition)
MOVEMENT
Jewels: 17 Jewels.
Setting: Lever Set.
Escapement: Lever Escapement.
Material: Nickel.
Layout: ¾-Plate Layout.
Signed:  Yes.
Conditions:  M  2  (The movement is in Perfect condition)