TW / THW hlau yog ib qho khoom lossis tso tseg, mos annealed tooj liab insulated nrog Polyvinylchloride (PVC).
TW hlau sawv cev rau cov thermoplastic, dej-resistant hlau.
THW hlau kuj yog thermoplastic, dej-resistant hlau, tab sis yog kub resistant, denoted los ntawm H nyob rau hauv lub npe.