WANCO Perforated Steel Cable Trays Wanco Perforated Steel Cable Trays are constructed using the highest grade of Electro-Galvanised Sheet Steel for Epoxy Powder coating and high grade hot rolled steel for Hot Dipped Galvanised coating. There are basically 3 types of Cable Trays construction: 1. Standard Type (Straight Flange) 2. Returned Flange – Type A 3. Returned Flange – Type B Covers are available upon request.