ESD Brushes are ideal for removing dust, dirt and left over materials from printed circuit boards (PCB) and other static sensitive components. Brushes minimize static charge generation and remove electrostatic charges to ground when held by grounded personnel Dissipative polypropylene black handles are able to remove charges to ground Resistance of conductive fibers: 10E3 - 10E4 ohms Resistance of dissipative handle: 10E5 - 10E8 ohms Fine bristles are mainly for electronics, especially circuit boards Bristles are a mix of conductive synthetic yarn and horse hair This item is stocked in Chino, CA.