... winding coils, etc. (Except the oil-immersed transformer) CertificationsProcess of producing Technical test itermsMaximum Overall Diameter, Conductor Diameter, Film Thickness, Conductor ... High Voltage Hole, and Pin-Hole etc.e.gProcess of PackagingPlastic bobbin of PT-4/ PT-10/ PT-15/ PT-25/ ... PT-60/PT90 to pack wires according to the size of wires. then packed with film, carton, pallet outside. ...