This is a crazy and rare LeCoultre Futurematic Porthole, ref. 502 from the end 50’s and was first sold in the USA. The Futurematic was produced from the beginning of the 50’s and had several different dial and case versions, but generally can be divided into two distinct types – normal sub-dials and portholes sub-dials. “Porthole” has a 37mm solid 10kt gold filled case, automatic bumper “hammer” movmement caliber 817 adjustable with the wheel on the case back, there in no classical crown built in. A feature of the movement is a lock that holds the swinging weight in place when the mainspring is fully wound. It also features a special 6 hour power reserve, allowing the watch to immediately function when it is put on, rather than requiring it to be wound first. This watch is running very good, power reserve and small seconds are working perfectly. New leather strap and buckle are not original to the watch.
Differential taxation §25A UStG.