Ordinary plastic doorbell sound built-in dual stereo speakers, sounds very clear and material selection of high quality industrial plastics fabrication, and units for homes, restaurants, factories, and other places of use. Plain plastic door minimum order quantity is 1, and it uses wireless installation design, reducing the trouble and expense of installation and accurate "RF ISO code" technology from interfering with each other. Normal aging of the plastic doorbell material does not, do not fade, corrosion-resistant characteristics, blister card packaging, wholesale reference price negotiable, Qty 60 kcal/pieces.