The Blackseal is one of the most successfully replicated Panerais on the market.  It simple design and lack of crown guard makes it vulnerable to the replication techniques the counterfeiters use.  Early replicas had the incorrect base movement, which more recent versions have the correct swan-neck movement which makes them much more difficult to detect.

Panerai 183 "Blackseal"

Genuine watch on the right. Genuine watch on the right.

Compare to Genuine Panerai PAM-183s on eBay

PANERAI PAM 183 K Black Seal US $4,295.00 (0 Bid) Auction Ends: End Date: Wednesday Sep-08-2010 7:11:45 PDT Add to watch list

PANERAI - Stainless PAM 183 I Black Seal 45mm Radiomir US $4,495.00 Auction Ends: End Date: Saturday Sep-11-2010 7:50:09 PDT Add to watch list

PANERAI - 45mm RADIOMIR SS PAM 183 Black Seal US $3,890.00 (0 Bid) Auction Ends: End Date: Saturday Sep-11-2010 8:02:05 PDT Add to watch list

Panerai PAM 183 Black Seal Radomir , Great Price! US $3,500.00 (0 Bid) Auction Ends: End Date: Tuesday Sep-14-2010 11:14:44 PDT Add to watch list