noun
railway crossing emergency button
A device installed at railway crossings that allows pedestrians or drivers to alert the railway operator in case of an obstruction or emergency.
踏切で車が立ち往生したら、すぐに踏切支障報知装置のボタンを押してください。
If your car gets stuck on a railway crossing, immediately press the button on the railway crossing emergency device.
Compound of 踏切 (railway crossing), 支障 (obstruction), 報知 (notification), and 装置 (device).