National shutter, 2 mm thickness, protects you from theft with a high security level, good insulation level, and complete protection from dust and light. The Spanish shutter has an excellent insulation level and less protection. It is installed on small windows on the first and second floors, etc. It is not recommended for large areas and windows overlooking the street. The Kuwaiti shutter has the same specifications as the Spanish one, but with a slightly higher thickness.