Female DB25 adapter cable (RS-530) to DB37 (RS-449 DTE), 10-inch length DB25 Female (RS-530) to DB37 Male (RS-449 DTE) Cable, 10 inch Length. RS-530 was designed to replace the bulky DB37 RS-449 connector. The CA107 cable allows any Sealevel RS-530 adapter to be used in an RS-449 application.