Supply of 110 kV and 35 kV insulators October 18, 2017 | Europe Tenders nternational competitive bids are invited for the supply of 110 kV and 35 kV insulators for Sokolac, Foča, Sarajevo and Novi Travnik substations located in operational area of Sarajevo. This content is available to only paying subscribers. Username or E-mail Password Remember Me Forgot Password