This is a very rare vintage stopmeter in great condition. As cars and the world changed i'm sure most of these found thier way to the trash can. I understand they were used for Sate Inspections from the 20's to the 50's. You may have the same question i had, what is a stop meter? They were used to measure the distance a vehicle could stop at different speeds. You placed the meter on the floor of the car, level it and then drive the car at any reasonable speed, it will automatically indicate the feet it took to stop. It is made of cast and stainless steel or chrome. One of the tags reads " A FULL JEWELLED INSTRUMENT" This unit looks really nice, i'm sure it did not see much service.