Fastener assembly for insulation blanket

A fastener assembly affixing an insulation blanket onto a substrate, the attachment assembly comprising:

• a substrate;
• an insulation blanket having a mounting hole;
• an attachment member including a base adhered to said substrate and a male threaded element;
• a cap fastener including a radially enlarged cap member made of plastic having a radial size and shape greater than said mounting hole, said cap member having an exterior side and an interior side, said cap fastener further including a second fastener element made of metal which includes a head and a metal female threaded element extending from said cap member's interior side projecting at least partially through said mounting hole to threadably affix to said male threaded element, wherein said cap member's interior side overlies and engages said insulation blanket in a region surrounding said mounting hole so as to affix said insulation blanket to said substrate;
• and
• said cap member encapsulates said head so as to prevent rotation of said cap member relative to said second fastener element, said second fastener element's extension extends from said cap member's interior side, said cap member's interior side having a substantially concave surface forming a circular recess surrounding said second fastener element creating a circular insulating cavity in conjunction with said insulation blanket.