Hot sell retro handset Volume control function Many beautiful colors to choose Use for iphine New product -- retro phone handsetMain features and technical parametersIntensity of tension>250kg; strong destruction resistancyGood flame retardancy and hand feelingAmbient Temperature: -30~+50°c               Relative humidity: ≤95%Atmospheric pressure: 80~110 kPa        Ambient noise: ≤60dBExplosion marking: ExdibBT6         Level of protection: IP65~IP67Working frequency: 300~3400 Hz        Good call transmission of the matching phone, 4.2-in-GB/T15279-94-compliantMain components:Shell made of PC                            Armoured cord or coil cord High strength steel rope                       Pierce-proof and hi-fi transmitter and receiverConnect the permanent seat of the case          Magnets or reed in some handsetsCustomer choice: Connector can be chosen according to connector series or designated by customers