B722 SNF AdvanceD SIOV Metal Oxide Varistors EPCOS B722 SNF AdvanceD SIOV Metal Oxide Varistors by TDK are high operating temperature (up to +125°C) varistors with high surge current ratings up to 10kA. The round varistor element is packaged in a silicone resin UL 94V-0 flame-retardant coating with tinned wire terminals. The high-energy AdvanceD Series E2 varistors feature high energy ratings up to 400J, a wide operating voltage range of 130VRMS to 625VRMS, enhanced resistance against heat and humidity [85°C, 85% r.h., 0.85 - VV (1mA), 1000h], and can be used in harsh environments.