The 25121WF0680T4E is a 1/2 watt 0.68 Ohm surface mount resistor from Royal Ohm. It is composed of a flameproof ceramic cement-filled epoxy body, a tinned copper lead wire termination, and a nickel barrier layer. It has a tolerance of ± 5% and a thermal overload coefficient of 5 ppm/K. This resistor is used in a range of applications including telecom, power electronics, security systems, and switch mode power supplies.