I got a piece of aluminum tubing from amazon https://amzn.to/3u4wONP (I'm sure cheaper locally) lined it up, marked one side and drilled it out (start with a very small bit then work your way up to the proper size.) I then put it on tight with no washers, marked the other side, took it off and drilled the other hole. Then installed with the washers and lock nuts, and used a hacksaw to cut off the excess. Maybe $2 from hardware store plus the $10 from amazon, pretty handy! With the nuts sticking out it takes a tiny bit of finesse to get the pannier on, but not bad. Nice to have storage that doesn't interfere with the kids. Front basket can be their school stuff and this pannier can have all their activity gear for sports or whatever.