MB-86EI is used for fabrication of EI30 fire-rated openable windows to EN 13501- 2+A1. MB-86EI is based on MB-86 system, and has excellent thermal, sound reduction, water resistance and air leakage performances. The MB-86EI combines the advantages of a classic window system with the properties of a fire partition walling – the construction meets all the requirements of the applicable regulations and standards, especially regarding energy saving and environmental protection, while ensuring proper fire safety. The system is classified as non-fire spreading (NRO)