Where can I buy or how can I make high quality jumper cables?
I'd go with the crimping kits and pieces from Hansen Hobbies.



I use their stuff quite often along with a set of their red/white/black AWG26 wire, the deluxe crimping tool, and whatever connectors the job calls for. They also have keyed and snap-locking headers too, so your customer doesn't install the header backwards.

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