I’m reasonably certain that Southwire tools are not made by or otherwise affiliated with Klein. Lowes got rid of brands like Ideal and Knipex to sell Chinese made knockoffs for similar prices. Since stocking up on Ideal low-voltage tools (missed the Knipex clearance due to Afghanistan) I spend virtually no time in the Lowes electrical tool section.
No electrician here - but my few looks at Southwire (a very big cable company) tools - said that they were made in China to compete at a lower price. Maybe they approached Lowes or the other way around to slot their tools onto Lowes racks.
Klein meanwhile seems to be still producing many of their tools in the USA - but multi-bit drivers now seem to be from Taiwan and some of their boring bits seem to be made in China.
I’m not sure if Southwire’s subsidiary company (Coleman Cable’s Woods Industries) still make their tools in the USA