It's one of the smallest pocket watches ever made.
In fact, it's to small to be wore in pocket and more suitable to be attached as pendant.
Diameter is less than 20mm, height without bow is 25mm, weight is 9,5 grams.
Very rare size.
Based on LeCoultre ebauche - Calibre 5, also known as Revolver-Calibre.
This Calibre was executed in quality "extra fine" and was produced without seconds hand in sizes from 6" to 8" and with seconds in sizes 8"-19"
This movement should be 6 lines and a smallest LeCoultre movement.
The dust cover signed "Geneve", should be by Genevan retailer.
The case is French made and bears 18k French hallmark as well as manufacturer's hallmark SG for "Societé générale des monteurs de boites" from Besançon.
Condition
The watch appears to be in good condition.
The movement works, but I don't guarantee time keeping.
Dial seems to be free from defects.
Case has minor wear.
Mineral crystal, original hands.