It works great and keeps excellent time. It is extremely clean and very sharp looking.Serial number is 181206, made in 1916-17. It is stem wind and stem set, lever escapement chronometer. Movement is marked Special with 8 eight adjustments as well as Patek Philippe and Bailey Banks & Biddle & Co. What a breath taking dial and hands. This dial is double sunk which is rarely ever seen on Patek Philippe pocket watches. This dial is not your typical white glass enameled, it is cream color glass enameled dial and in MINT condition. Hands are in Mint condition also. Thank you and very best of luck. The item "Patek Philippe antique pocket watch movement 41mm marked Special" is in sale since Tuesday, July 24, 2018. This item is in the category "Jewelry & Watches\Watches, Parts & Accessories\Pocket Watches\Antique". The seller is "watch-art" and is located in USA. This item can be shipped worldwide.