This is an after-market car aerial to radio coax cable lead that screws on to the aerial neck of many original equipment OE aerials, and plugs into the back of most car radios. It has a female/internal thread on the aerial connection end and a male push-in jack plug on the radio connection end, or into an extension lead.
Overall length is 1.5 metres (5 feet) which is adequate for most front wing/fender mounted aerials. The screw on connection to the aerial antenna neck was as used by most European vehicle manufactures from the 1970's including BMW, Ford, Jaguar, Mercedes, Saab and Volvo on most wing/fender mounted manual and electric aerials.
The screw on female connector is the type most vehicle and aerial antenna manufacturers use where there is a connection on the aerial, as opposed to an integral lead.
We can supply extension leads of various lengths at additional cost if required.
Specification:

• Aerial Connector M10 x 0.75 female thread (screws onto aerial neck)
• Radio Connector DIN41585 Male (Plugs into radio or extension lead to radio)
• Good quality coax lead with excellent shielding.
  

We also have this lead available as a 4.5 metre (approximately 15 feet) for aerial antennas mounted on the rear wing/fender.