Freehub retaining nut

[nstrug]

Hi -

I have to switch over between a Campagnolo freehub and a Shimano one regularly and have now trashed two retaining nuts. The problem is that the walls of the nut are incredibly thin where the flats are and they are extremely easy to distort. It doesn't help that the nut is made of cheese.

I've just ordered 3 more from Elite, but I'm getting a bit bored of this - does anyone have any suggestions for avoiding this problem? I'm using the proper tool of course.

Cheers,
Nick