PIcked this up a while back. A Dietz 7-40, with an SAE W3 80 and a motor date of 8/88. Can you belive 1988 is 31 years old. Not a bad little light that works very well. I wonder if they were used very much except for utilities.
Here you have a few pictures I found of vehicles using the Dietz 240, 7-40, 240-1, 7-41.
Seattle, Washington Police Department.
A mix of Federal TwinBeaconRay’s and Dietz 240’s.
Oregon State Police.
New Castle County Police Department, Delaware, I believe.
Unknown Sheriff’s Department where a city police ”meter maid” writing parking tickets on the Sheriff’s cars.
Hopefully a funny joke for the photo but not so uncommon with rivalry between departments. Stupidity!
For those who do not know the difference between Dietz 240 and 240-1 is that the 240 is for roof mount and has an open bottom with a black rubber gasket and the 240-1 is for roof bar mounting with a stainless steel mounting plate at the bottom that was secured by four screws.
The 7-40 and 7-41 are the same lights as the abow but with the new model numbers introduced by Dietz in about 1970-71.
It is easy to recognize these lights because the name tag on the 240 and 240-1 is on the base but on the bezel on the 7-40 and 7-41.
The 240-1 and 7-41 has four mounting screws near the bottom rim of the base to fasten the mounting plate.
The 240 and 7-40 could of course be mounted on a roof bar with a user supplied mounting plate.
If they are mounted on a bar and there are no screws on the lower part of the base, they are 240s or 7-40s.
As I mentioned earlier, the blue coloured lens was of a light blue colour before 1980 but of a more normal blue colour after that year.
One more Oregon State Police car with one center mounted Dietz 240-1 and two red Dietz 250 lollipop lights on a Dietz roof bar.
The car seems to be an early 70s car but the Dietz bar is a 60s bar that was replaced in around 1970-71 so I assume that the model numbers are the old ones.