The Decot is among the oldest civil warning sirens in the world; dating back to the early 20th century and still in service and production today. Most early Decots resembled buckets with vents in the side at the lower part of the housing. Newer Decots resemble street lights (only a certain type of street light). Some have non-transparent covers hiding the choppers; and some have clear covers; exposing the choppers. The Decot is not manufactured by either Federal Signal or Alerting Communications Of America.