Glashütte Original

I have had this watch almost a year now and not yet changed the strap. I did yesterday and love the result. Slightly dressed down and a bit more nautical. I will leave it like this for the next year, I do believe ...  

What strap is it? Is it 3rd party?

Gives the watch a bit more casual yet classy look!

I plucked it from my 1846 Chronometer and it is a perfect fit on the Glashutte.