Very Good Bracket.
I've a Optoma HD65 projector and like others say, I needed a pack of M3 bolts and small washers to attach the two together. Got mine from Halfords.
One thing I really did like is that the centre of the bracket plate is hollow (see picture). This allows you (if you want) to drop the HDMI cable through your ceiling, through the bracket itself, into the back of your projector. Also you can thread the power supply lead (kettle style) through too it too. Once all fitted, the power lead and HDMI cable are hidden from coming through the ceiling - Brilliant!