The Balestro's PBP polymeric distribution surge arresters have an advanced envelope system for the ZnO varistor stack, the ISOFIVIN (Pat. Pend.). This new system improves resistance to weather conditions (no moisture ingress) and mechanical characteristics, with high cantilever and torsioval strength. Over this envelope, Balestro has developed its polymeric housing with silicone rubber, highly resistant to UV radiation, polluted environments and all weather conditions, specially recommended for high polluted areas. In this feature, the silicone rubber has a particular advantage to other polymeric materials: Its hydrophobicity, that allows water-repellent characteristic to the arrester housing. The Balestro's PBP polymeric distribution surge arrester are equipped with a disconnector device carefully developed for coordination with the over current protection of the distribution lines.

Its time x current curve coordinates the operation with fuses type 12K (12A, fast type). Balestro has a modern test laboratory to perform, beyond of routine and acceptance tests, design (type) tests like combined operation duty cycle, high current and long duration current, accelerated ageing in zinc oxide varistors, dielectric test (both of impulse and A.C. tests), partial discharge tests and others.

The Balestro's PBP distribution surge arresters meet both IEC 60099-4 and ANSI C62.11 standards requirements.