... High strength of thread Fiberglass winding tube for power Transformers/fiberglass round tube/pipe Our tubes are divided ... hollow insulators, surge arresters, HV swithes, current transformers and power transformers Features: Fiberglass Winding Tube 1.Inner Diameter:14 ... Test: SGS, other tests in National Labs3.Application: Power Transformer,Current Transformer,Hollow Insulators, Bushing, Surge Arrester, ...