I have had to re-list. READ DESCRIPTION! Original IWC Navy (dark blue) quick release strap 21mm lugs with steel rivets and a IWC bi folding (butterfly) clasp 18mm using classic spring bar and is not quick release. Both are original, however the clasp isn't what you would normally see on pilots model. It is ideal for any other 18mm buckle width straps as well as this one. Cheers
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