The original Mare Nostrum is one of Panerai's most rare watches. It was designed for deck officers of the Italian Navy in 1943. The watch however never made the intended production process and - as far as documented - only three prototypes were made. It was unknown what happened to these three prototypes and all documentation was lost when Florence was flooded in the sixties - until one of the watches was offered for sale at Christies in 2005. Officine Panerai bought the watch for their museum for the sum of 85,000 EUR.

Panerai did already reproduce the Mare Nostrum in 1993 but the new 2010 PAM300 is made to more exactly meet the specifications of the original Mare Nostrum. The case of the PAM300 has the same shape and size (52mm) as the WWII original and the dial looks very similar. Except that tritium was used on the indices of the original watch. The watch - like the original - has a sandwich dial. The color of the luminova on the new PAM300 does seem to match the color of the original watch quite closely. Panerai did a great job on the olive green canvas strap too. The PAM300 has a Panerai OP XXV movement - based on a Minerva movement (photo below). The original Mare Nostrum had an Angelus movement. You can admire the beautiful movement through the crystal case back. The original Mare has a closed case back.