The 621KD10 is a radial leaded varistor manufactured by Liown. It has a 1.025kV rating, 0.4W power dissipation, 72J impact energy, 160pF capacitance at 1kHz, 505V, 385V and 620V working voltages, and a 2.5kA pulse surge current alternate rating. It is RoHS compliant and suitable for various electronic circuit protection applications.