Fuse, 300 A, 300V AC, 160V DC, Class T, A3T Series, Nonindicating, Very Fast Acting, Body Style Blade, Nonrejection, Interrupt Rating 200kA at 300V AC, 50kA at 160V DC, Fuse Size 2-3/4 in L x 1-5/16 in dia, Length 2 3/4 in, Diameter 1 5/16 in, Equivalent Brand and Series Bussmann JJN, Edison TJN, Littelfuse JLLN, Mersen A3T, Equivalent Series A3T, JJN, JLLN, TJN, Compatible Fuse Block Series 3TFB, 6TFB, Body Material Glass/Melamine, Single Element, Standards UL/CSA Very-fast-acting nonindicating UL Class T fuses open circuits even more quickly than fast-acting fuses when exposed to overloads and short circuits. They're commonly used to protect solid-state electronics. These very-fast-blow fuses are highly sensitive to changes in current flow and don't tolerate temporary overload currents o.