Die Cast Zinc Chrome Plated. Die cast zinc construction with a mirror finish chrome plating will accept any standard antenna with 1" - #14 threads. Designed with an integral feed system for Loran cable. Standard case: 5.4-3/4", B-2-1/8", C-3-5/8", D-1-7/16", E-2-15/16", Fastener-1/4"