1: Optimal Sealing by O-Ring Highly durable Teflon O-Ring was used and special coating was done at the contacting point of O-Ring to ensure perfect Sealing and secured operation at fire detecting. 2: Shock proof structure with steel ball support method With 8 steel ball support structure for shock esistance, it Is reliably safe from external impact and free from damage And leakage 3: Low Assembly Load By minimizing the assembly load with o-Ring Sealing Method, safety is secured with low pressure inside the Head. 4: Excellent Design As the head is installed in the building, aesthetic design By minimizing heat detecting with small head was made.