Cal Test Electronics CT4008 4mm Sheathed Banana Jacks provide a ø4.8mm quick connect tab and operate up to 5kV when used in non-category environments with transient overvoltages up to 2kV. The CT4008 banana jacks fit into plastic and metal panels fixed with a 14.5mm hex panel nut. These banana jacks should be used only with the CT3018 or CT3020 long-reach high-voltage test leads. The CT4008 banana jacks are available in red or black color options.