The mount features a negative taper, such that pulling on the duct increases the clamping force.
You will need 4 50mm M4 machine screws, and a 125mm diameter screw clamp to fasten the ducting on.
Colour will depend on available material, but will normally be either grey or black.
Price is AUD $15 each, plus $9 postage for any quantity (within Australia only).
Payment accepted in AUD, BCH, ETH, LTC
Some pics here:

