ZF Factory Men'S and Women'S 15550 Watch Small Size 37Mm Fully Automatic Cal3120 Mechanical Movement 50Th Anniversary Top Craftsmanship Qualityfree shipping Good service Process and manufacturing technology: Mechanical watches are usually manually assembled by watchmakers, requiring a high level of technology and craftsmanship. This makes mechanical watches a form of handicraft, as they combine the exquisite watchmaking techniques with artistic design. Accuracy: Some advanced mechanical watches, especially Swiss watches, have very high time accuracy. This is due to exquisite watchmaking