I-THHN THWN THWN-2 Ucingo lufanelekile ukusetyenziswa njengesixhobo somatshini, isiphaluka solawulo, okanye i-wiring yesixhobo.Zombini i-THNN kunye ne-THWN zine-PVC yokugquma kunye neebhatyi zenayiloni.Ukufakwa kwe-PVC ye-thermoplastic kwenza i-THHN kunye ne-THWN yocingo ibe neendawo zokunqanda ilangatye, ngelixa i-nylon jacketing yongeza ukuchasana neekhemikhali ezifana nepetroli kunye neoli.