"If you need a wall bolt then these are the ones to use. Price is better than getting them from the big DIY stores. However, I got a couple of packets recently that had wall bolts without the Fischer 'fish' logo on them and they were a different wall bolt. Instead of a 16mm hole, they needed a 17mm hole. The collar was a whole millimetre bigger. I don't have 17mm drill bit, so I took them back and got them exchanged. Moral of the story is make sure they have the Fischer 'fish' logo stamped on them."