1. The actual distance is 1000 meters. The first floor to the eighth floor 2. The appearance is thin and the thickness is 18mm. Similar products on the market are than 22mm thick. It feels good to hold them 3. The battery is a 2000mA lithium battery. The external unit and the indoor unit are both real 2000mA batteries. The external unit works normally. Press five s a day, talk for two minutes at a , work for about 8 months, and the indoor unit works for about 1 week, 4. The keys are made of plastic+silicone structure, and the surface is made of high-gloss technology, which has a super . Compared with the counterparts, the keys are made of all-rubber, which has no grade and feel. 5. Intelligent and humanized design, with intercom light and power light display, customers can see at a glance