OK , I name it Ralph.
Blurry McBlur
Part of a seat belt because it looks like a great way to achieve uselessness. There is no way to fix them once they break. I don’t know.
That is the strap used to hold the spare tire jack in the storage mount under/behind the seat.
I thought it was a strap off a bike rack. But then I made my own with parts from the canvas shop. Either two on the back of the car or two on the back of the camper and one on the front depending on destination.
Incidentally, I made one that fit in the trailer hitch before they became available. We were at Disney and one guy looked it over pretty good and was curious. About a year later they were on the market. Always wondered.
The inside of a seat belt buckle receptacle for an older vehicle.
Or, b e e r bottle opener with anti theft strap. The censors did not like the word b e e r when posted without spaces
That was my guess, but my seat belts work and I can’t figure out where it would go.
I bet you’re right. I’ll look at it in the morning. Thanks.
Probably an elastic hold down strap of some kind… Now you tell us, do you know what it is or are you just trying to figure what it is after you found it under your car and you ae trying to figure out if your car is safe to operate while you are holding it in your hand instead of it holding some critical part in place… 
