This is the special strap that was developed for the Novem Moonphase watch.
It has a 20mm lug width but widens out after the lugs to 24mm, features a padding on both straps for added volume, and a decorative hole punched pattern.
It's quite the statement. Even the buckle is custom and larger in size.
Works really well on the Novem, and any other chunkier watch with 20mm lug width.
Also available in Black.