Firelock® fire-resistant Sliding door with escape door, type BSL60, and Firelock® ASG sunken floor socket. This Automatic Sliding Door Guide can be used with fire-resistant sliding doors wider than 4,500 mm. The sunken floor socket goes into operation in the event of a fire alarm or power failure. A specially designed steel form emerges 20 mm from the sunken floor socket to ensure correct guidance from the fire-resistant sliding door to its end position. This lock is necessary to prevent the sliding door from bending in case of fire.