2.3 mm wide. The top one is 76mm in length. The bottom one is 51 mm in length.
The big hole in the bottom is 57mm long and about 9mm wide (couldn't get my calipers in there because of the license plate bar which I chose not to remove!).

The Original Ken
11,000 miles.

2014 BMW R9T
2005 Saabaru
2005 Saabaru