1、Sonoff 4CH Pro & 4CH Pro R2 are 4 gang WiFi switches. 2、They support switching among 3 working modes: interlock/self-locking/inching mode. 3、They integrate with a 433MHz RF receiver module, making them possible to be controlled by RF Remote. 4、Users can remotely turn on/off the connected lights/appliances by iOS/Android App eWeLink or 433MHz RF Remote. 5、They can create 8 enabled single/repeat/countdown timers to automatically turn on/off at the specified time. Features: Sonoff 4CH Pro & 4CH Pro R2 are 4 gang WiFi switches. They support switching among 3 working modes: interlock/self-locking/inching mode. 4CH Pro supports to set 0.25-4s delay in inching mode,  while 4CH Pro R2 supports to set 1-16s. They integrate with a 433MHz RF receiver module, making them possible to be controlled by RF Remote. The Sonoff 4CH Pro smart switch is DIN Rail mounted. Users can remotely turn on/off the connected lights/appliances by iOS/Android App eWeLink or 433MHz RF Remote. They can create 8 enabled single/repeat/countdown timers to automatically turn on/off at the specified time. The timers can run themselves even when the network is unavailable. To let the devices be controlled by their family, users can simply share the devices with their accounts and allow specified timers permissions. They can even create some scenes or smart scenes to trigger ON/OFF the switch. Specification: Item Type: 4CH Remote WiFI Remote Control Switch Enclosure Material: Fire-retardant ABS Operating Voltage Range: AC 90-250V / DC 0-30V  Input Voltage Range: AC 90-250V / DC 5-24V  Operating Temperature: -20℃-70℃ 4-way Total Load: 16A +3500w Control Method: mobile APP Support System: Android / ios Controllable Line: 4 way Transmission Method: wifi communication network Size: Approx. 14.5 x 9 x 3.5cm / 5.7 x 3.5 x 1.4inch Weight: Approx. 243g Remote Control Battery Type: CR2035(included) Package list: 1 x 4CH Remote WiFI Remote Control Switch(With remote control)