The adapter is marked CCIR RL 730 DB.
The base measures 1 3/4" X 2 1/2" and the inner opening is 1 5/8" X 7/8".
From the estate of Joseph Racy, a high caliber RF & Microwave engineer.
Please reference our part number SL525
Posted by 968460185@iowa-industrial.com (actual email hidden).