Material:Brass Frame,Casting Technology Creating Simple and Smooth Linesn8 Wrap Coils Set Liner;33UF 50V of Liner CapacitornSpring:High Flexible,Strong Elasticity,High Hardness,Not Easy to WrecknContact Screw:The Copper Stick Easy Conductive,Resistance to Blunt Damage,Convenient AdjustmentnGood Point:Stable Working Speed and Hitting Amazing Hard with Less Power,High Strength Allow It to Work for 8 Hours at a Stretch Without Any Heat,These Machines Run Super Solidn