CLASSIC SKELETON DESIGN: Stainless case and exquisite engraving on the case removable stainless brass tone chain with a clip at the endnHAND WIND MECHANICAL MOVEMENT:Functions without a battery; powers with mechanical movementnHOW TO WIND THE WATCH:Please wind the mechanical watch by turning the crown clockwise for 15 to 20 complete revolutions every day. Over 20 times may do harm to the watch mechanism.nWATERPROOF FOR DAILY USE: Daily use waterproof, not suitable for underwater activities - such as shower, swimming, ect.nHIGH COST-EFFECTIVE:Good quality with low price, great gift for your friendsn