Weight is 17g. A quality product. Frequently used on boats and caravans. The spring is very strong, but there is a thumbnail groove in the lid to assist opening. These ones have three screw fixing holes in the base plate.
I bought these to replace existing, scratched escutcheons on my car. These turned out to be a great fit and exact copies of the ones I wanted to replace. The only criticism is that they did not come with nuts and bolts to fit them. I was able to use the ones I took off the ones I was replacing.