[MrForbes]

We had a nice setup in 2008 using fanged elevator bolts (from McMaster Carr) in the bumpers, and coupling nuts to hold them on. And we even made the bumpers well enough that we can use either side bumper on either side, and either end bumper on either end. Too bad we couldn't make it work so well on the 2009 robot. And too bad I didn't get good pictures of it.