Picatinny Ring Adapter (x3) for 19mm (wide) barrel
SKP included, enjoy.
Postnote: After actually attempting to attach a few things to this, I realise that the mounting points are a little too close to each other... so it's unlikely you would get 3 devices on this.
Two on either side would be fine, but most things I have mounted on the top, didn't leave enough room for either side mount to be used.
Other than that, it's pretty awesome. I ran a small bolt through the hole, and spring of the ABS ensures the nut stays firm.