Features: 1)Hermetic metal case with ceramic insulator 2)Hermetic glass-metal seal 3)DC motor controls 4)Synchronous motor eccitation A)IT(AV)=10-300A B)VDRM/VRRM=100-2400V C)Conform to GB4940-85, JB5838-91, JB5839-91and IEC international electrical committee standard. D)Used in Controlled power supplies, switch and thermal control and so on.