Model and year

I´m new over here and just inherited a IWC gold watch from my grandfather and I want to know the year of assembly and model. has been at least 40 years in a safe box and works perfect! just great!! Thanks for your help.

Firstly welcome to the forum and with your Grandfather's fine piece. After 40 years of being unused I can promise you that the oils are dried out. Please get it serviced sooner rather than later. As to the model I will leave it to others to identify. This is a job for a good watch maker or for the ultimate service it can be taken into your nearest IWC authorised dealer. Most watches this old will be sent back to IWC Schaffhausen and will come back looking like new, but it does cost but your watch looks in good condition apart from dry of lubrication.
After 10 years since my father died I got his watch restored and serviced and the difference in how it performs was amazing, his watch was hand wound and lasted about 12 hours before stopping, it now lasts over 35 hours. That is the difference when the watch is stripped, cleaned and lubricated by a proper watch maker.

Someone must know this model?

It looks like a Cal 853 from the mid-60s. Great movement and obviously in superb condition. This link from MF's catalogue project may be helpful.

1966 IWC catalogue

Thanks for your help, now I know the real treasure I have.

Thanks for your help and recommendations.