Simple Mobile by T-Mobile. Shows 'TFW' on the label (Tracfone Wireless) though, and if you plug the SIM into an unlocked Galaxy S5, it shows 'Verizon Wireless' up top. Apparently, any of Tracfone or other MVNOs default to Verizon or AT&T regardless of the actual carrier. Red map on box and all.
Odd bonus, while AT&T killed their EDGE (2G) network back in 2016, T-Mobile still has an EDGE tower near me, at a junkyard I visit. It can make calls on it but no data. Tower must just be 'on' but nobody home. Dad before he died in 2016 was able to keep using an iPhone 2G via T-Mobile. No text, no data but he only used it for voice and wifi for Safari.
Still, unlimited talk, text, and DATA, $25/ month, and the iPhone 6S costs $149, great no-contract deal.