Wrist Band make directly contact with skin, through button on the metal plastic buckle and grounding kits, transmit the electrostatic from skin. Wrist band is made of various conductive compound materials, such as silver-gilt fiber and elastic nylon thread, stainless steel fiber, conductive plastic buckle, also have metal wrist strap with metal stretch watch. In despite of which material, wrist band must be satisfied with two points, one is wrist band (be closed to skin) volume resistivity with ¦Ñ V¡Ü 102¦¸ Cm, second is wrist band must be elasticity or can be adjustable, be suit for different wrist can be closed tightness to skin. Metal plastic buckle likes plate, joint wrist band and grounding cord, adjust the contact between wrist band and skin. There are three types of button with 4mm, 7mm and 10mm.