I know nothing about watches so I am coming straight to the experts for help.
My brother found this watch while walking on the beach in Newport Beach, Ca. The part of the band that attaches to the watch had broken. He put an ad in the paper but no one responded so he gave it to me.
The front reads, "Panerai Automatic Swiss" on the bottom and "Luminor GMT". The back reads, "Officine Panerai Firenze 1860 Divers Professional OP 6541 BB 000000 C000/500 Stainless Steel 1000m". The band is rubber and the watch is very heavy.
Any help would be deeply appreciated