6644 features 2 - 1K 1/8 watt 5% carbon film resistors in our 50R brown case with 2 blue and 2 black 12-inch leads. The ideal position for the end of line resistor (E.O.L.) is at the farthest point from the panel in the zone loop. This will confirm the integrity of most, if not all, of the wiring between the panel and the last device installed on the zone loop, thus preventing any intentional or accidental compromise of the security zone loop. The closer the E.O.L. is mounted to the panel in the wiring loop, the greater the possibility of compromise of the unprotected loop wiring after the resistor position