What banks still use KTT?

Oh, dude, you're asking about KTT, huh? Well, technically, KTT stands for Key Tested Telex, a secure way to communicate financial information between banks. Some banks still use it, but it's kinda like asking who still uses fax machines in the digital age, you know what I mean? It's like a vintage banking communication method, but hey, if it ain't broke, why fix it?