805engineer said:The early design had 6mm "Torx" pan head bolts and nuts. ?This was done mostly for appearance (look cool and match the roof attachments). ?After the Escalade EXT was done with hidden plastic clips, the design was revised to the plastic "scrivets" with phillips heads. ?The attachments are only to hold the edges of the inner and outer sail panels together for a tight fit at the edges. ?Tightening the original bolts actually had a tendency to make this gap uneven.