This Tiny Strap Saves Electronics From Disaster! An ESD strap (Electrostatic Discharge strap) is a device worn on the wrist or ankle to prevent static charge buildup on the body from suddenly discharging into sensitive electronics. The human body behaves like a small capacitor that can accumulate thousands of volts through triboelectric charging (for example, walking across a carpet). If this stored charge suddenly discharges into a microchip, it can destroy the delicate circuits, which often op