In-house caliber BM13-1975A, 120 hours / 5 days power reserve. Accuracy -4 / + 6 sec. per day. Service interval + 5 years. Antimagnetism up to 1500 Gauss. Steel case semi-transparent sapphire crystal dial. Water-resistance to 100 meters. Baume & Mercier Fast Strap tool-free quick-change system.