1.Double-shield 2. cold press 3.F head 4.Without liner 5.Material:copper,USE:RF connector 1.The material uses copper rod with type 59-1, surface treatment of nickel plated. 2.Cold press series products all after heat treatment, will not craze when cold press. 3.Sealing ring choose ZY-850 type silicone rubber XY-024 -5 / -7 Xuanyi cold press F head Connector