Case is in sapphire Crystal at 45mm. Manual winding movement calibre BR-CAL.206. Moving skull when wound by hand. Crystal Sapphire with anti-reflective coating. Water-resistance 50 metres. Unique Piece To be offered at Only Watch 2021 auctions conducted by Christie’s on Nov 6, 2021 Estimate 90,000-110,000CHF Sold for 220,000CHF