Roger Long wrote:
I just got some do-it-yourself plugs for my Garmin GPS. I need to run
a 12 foot cable without splices so I can thread it through some small
holes and difficult to access spaces. The longest premade cable you
can buy seems to be 8 feet.

I thought it would be a simple matter to find some black, four (or
more) conductor cable with stranded wire but it isn't.

Does anyone know a source or type specification for the proper cable
to use?

In the US, Radio Shack, in the UK, Maplin Electronics. It's only data cable
(telephone cable).