High retention force fastener

A fastening system comprising:

• a first substrate having a fastener-passing bore;
• a second substrate having a fastener-passing bore;
• and
• a fastener comprising a metal clip and a plastic insert, said metal clip comprising a body having opposed substrate engagement features extending therefrom, an insertion stop plate spaced apart from said engagement features and plastic insert locking tabs extending from said stop plate, said plastic insert comprising a head and a leg extending from said head, said plastic insert further including metal tab engagement features extending from said head for engaging said plastic insert locking tabs of said metal clip and for locking said plastic insert against movement out of said metal clip, said plastic insert being substantially insertable into said metal clip between a first, pre-insertion position in which said plastic insert substantially extends out of said metal clip to a locked position in which said plastic insert is substantially inserted into said metal clip;
• wherein said metal clip is U-shaped and comprises two sides joined by a connector, each of said sides including a pair of said substrate engagement features.