Load-distributive washer for use with compressible material

A resilient load-distributive washer useful in conjunction with a headed mechanical fastener to secure a first compressible material to a second base member, said washer comprising an axially extending projection which has a length that extends into but is less than the thickness of the compressible material to be fastened;

• a load-distributing flange extending laterally outwardly from one end of the projection, the other end of the projection being free;
• a throughbore positioned along the central axis of the washer and extending through the projection and the flange, at least a portion of said throughbore having a first internal lateral dimension exceeding the maximum lateral dimension of the head and a length that is at least equal to the height of the fastener head;
• a portion of the throughbore nearest the free end of the projection having a second smaller internal lateral dimension forming a bearing surface for the fastener head;
• an integral flexible and resilient ring positioned above said portion of the throughbore said ring having an inner lateral dimension less than the maximum lateral dimension of said fastener head and sufficient flexibility and resilience to permit passage of the fastener head while delimiting the relative axial movement between the washer and the fastener.