This is a Marine mount adaptor, it allows the use of models TG-3, TG-4-ms or MSN, TC-3S or SH to be mounted on a standard marine lay down mount. It is threaded on the top. 1 1/4 inch pipe thread and the bottom 1"-14 inch pipe for the mount.It also has an oblong hole in the material.
There is one in gray plastic $6.99
There is one in stainless Steel $9.99
