Rectangular standard doorbells are packaged in sucker cards, with built-in stereo speakers that produce clear sound. They are powered by batteries and have a minimum order quantity of one piece or more. Each case contains 60 cards. The rectangular standard doorbell features a wireless installation design and precise "co-frequency different code" technology to avoid interference between each other. It is made of high-quality industrial plastic. The rectangular standard doorbell has a rectangular design with a combination of blue and white colors. The material is characterized by non-aging, non-fading, and corrosion resistance. It is suitable for use in family, restaurant, hotel, and other venues. The wholesale reference price is negotiable.