Ah yes well spotted. I've just got a bolt out of the van and it is quite disappointing actually, the socket attachment on the bottom is 13mm, and the wanky "hex angle" on the top in the head is the 17mm....
I'll have to try it, but first impressions are it is w***, other than that, its a really nice bit of kit, but maybe the 17mm spanner will prove me wrong! Obviously designed for c***** anchors mainly.
Its also powder coated stainless, so should far outlast the petzl ones in a mine environment