A recreation of the Federal Signal 500 siren which comes in many configurations with this model being 8/12 port and sourcing my chopper from my model 2. The other version I built has the cone like intake and a bigger chopper. This siren was produced in the late 1950s and sported a 8/12, 9/12, 8 - 12(DHTT), 8, 12 and 10/12 port configurations with there also being a dual horn two tone (DHTT), single horn two tone (SHTT) or single horn (SH) and they later were renamed BT, AT, A. This is a recreation of the non-cone intake federal 500 siren.