I purchased some of these for some AChat 204 speakers. For the price, I was expecting the brackets to be flimsy and bend easily. However I was wrong! These are very sturdy, heavy brackets which securely hold the speakers without flexing or bending. They come with padded spacer washers, and the correct bolts to attach to the speaker.
If you are using Speakon connectors for the speakers, rather than screw terminals, be aware that the speaker will not point 'straight out' as the Speakon connector sticks out past the bracket. Other than that - they're great. The centre hole will also take a M10 bolt, so you can easily stick a hook clamp on the bracket to attach the speaker to scaff tube.