I stand corrected. I understood the resistor that is in-line in a grounding strap to be a fuseable resistor - designed to open in high current. Jean provided a very good explanation. Joan Rapier [log in to unmask] That <wrist strap> cord has a built-in resistor in it so that you, when you wear it properly, are connected to ground through a large (1 megohm or more) resistance to limit any fault current through your body to a few microamperes (I think 25 miliamperes can cause the heart to defillibrate and 50 milliamperes can stop the heart). If you use a wrist strap cord as a grounding device, the unit is NOT directly connected to ground and if a fault current exists in it, when you touch the circuit, your body (approximately 10,000 ohms impedance) will become the path of least resistance and . . . well, you can guess the rest of the story. The PCBUILD web site always needs good submissions. If you would like to contribute to the website, send any hardware tech tips or hardware reviews to: [log in to unmask]