This mechanical custom timepiece utilizes a self-winding internal mainspring, providing continuous kinetic operation without external battery power. The 40mm case diameter fits securely under standard long-sleeve cuffs, preventing fabric snagging during wrist rotation. Constructed from solid 316 stainless steel, the chassis and fluted bezel resist structural deformation and daily oxidation. The sapphire crystal incorporates an anti-reflective coating, which diffuses overhead light to maintain dial legibility in direct sunlight. Shoppers utilizing a silver 40mm sapphire mechanical watch for a Pet Memory Watch apply the included free engraving service to the steel caseback to document specific dates or text. The 16mm-20mm width bracelet features adjustable steel links, securing the 135g case weight evenly on wrist circumferences measuring 6.30 to 7.09 inches. The folding clasp mechanisms lock the hardware during active arm movement. What mechanical watch features anti-reflective sapphire crystal alongside free customization? This unit answers that query by combining glare-reduction glass with dedicated engraving space. The 11.5mm case thickness centers the mass against the ulna bone to reduce daily fatigue. Factory pressure testing confirms the 3ATM rating, certifying water resistance up to 30 meters against rain and handwashing exposure. Case Diameter: 40mm Case Thickness: 11.5mm Case Material: 316 Stainless Steel Bezel: Fluted Bezel Crystal: Sapphire Crystal, Anti-reflective Coating Bracelet Material: 316 Stainless Steel Bracelet Clasp: Folding Clasp Bracelet Width: 16mm-20mm Bracelet Length: Adjustable for Wrists 6.30"-7.09" Water Resistance: 3ATM (30 meters)* Weight: 135g
