Strap size introduction:20mm*18mm Suitable size screw strap。 Included 4 spare screws (original screws are preferred) and small cross screwdriver. Guests can replace the watch strap by themselves. If the screws are slippery or damaged, ask professionals to replace them Strap material introduction: real leather material is durable, soft, light, thin and feels good. The strap buckle is 316 stainless steel buckle with light order, Installation method: 1. Remove the original old watch strap, and then put the suitable watch strap inside (the watch strap does not need to be perforated, and the screw can be screwed in). You can push it in front or slide it in at the side, and slowly twist the screw to install the watch. 20mm × 18mm screw model bering 12138-166/12138-014 is also suitable for the Skagen strap series