This fuse is stamped on the flat end: CAT. NO. 301143 23 KV AMP 5E TCC 129-5 7-77 all the way around brass cap. Other cap is rounded slightly on end. This fuse has some sort of liquid in it and a spring. It is 12-7/8" long and the bras caps are 1-1/8 " embosed one, and 1-1/4" rounded one.