The Murata BLM18KG300TH1D is an 0603-sized ferrite bead. It has a 30 Ohms impedance, a 5A dc current rating, and a DCR (direct current resistance) of 0.01 Ohms. It is designed for use in power supply lines, and is auto-powered for easy installation. The bead serves to suppress electromagnetic interference and reduce EMI. The ability to work in high-frequency applications also makes it suitable for use in data communication networks. The small size and low power consumption make it an ideal choice for use in devices like smartphones and tablets.