Collar Back Plate
A 1mm aluminium back plate, designed for use with the heatproof Silicone Collar (master flashing).
Combined together, these items clamp onto the canvas, sandwiching the canvas between the two.
The aperture for the flue pipe can then be cut to allow the fluepipe to pass through the canvas roof. Suitable for use with fluepipes with a diameter of 102-178mm / 4"-7" diameter.