S | RT9908 window intercom Anti-interference Volume control Use 4-core shielded wire Freely adjust internal and external volume Little interference and no noise Don't worry about not hearing guest's voice Flexible microphone Configure 3M adhesive Designed with metal hose, durable Can be directly glued to the glass Support multi-ante adjustment Solid and reliable Automatic calmness Integrated design Dedicated side sound processing chip One-line connection with the host Effectively improve howling Automatic