Introducing the GSM Multi-Household Outdoor Unit Model B502, the perfect solution for managing multiple households with ease. As a factory, we guarantee top-notch quality and functionality with this product. The B502 allows you to remotely control up to four gates or doors, making it ideal for communities or large estates. Its innovative technology allows for up to 999 authorized users, each with their own unique access code. With its durable design, the B502 is built to withstand even the harshest weather conditions. Upgrade your security and convenience with the GSM Multi-Household Outdoor Unit Model B502.