It’s useful for DC parasitic load tests and troubleshooting GFCI nuisance tripping
I found the splitter at https://www.amazon.com/gp/product/B07YH8N326/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1 for $49 and just ordered one
I found the splitter at https://www.amazon.com/gp/product/B07YH8N326/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1 for $49 and just ordered one