TELEPHONE ALARM OR LED ALARM, PSTN ALARM, ALL IS MADE BY OUR FACTORY UNDER RELIABLE QUALITY AND LOWEST PRICE,EX-WORK PRICE ..ETC DIY, Easy-to-use and operate.cost-effectived. remote keypad avaliable that supposed to install at the front door.Learning code to easily communicate new sensor or detector, suitable and helpful for home and commercial building. OEM/ODM welcome1. Wireless frequency: two ...