10mm x 100mm (Pack of 100) Plastic Insulation Fixing Hammer Driven Fastener with Plastic Covered Metal Pin for Concrete and Masonry 57.11

I used them for retaining filter media fabric in my boarders; they work perfectly

These are good quality and the metal pins are pretty robust. Only managed to break one so far when drilling the hole too short. I've used them both for rigid wood fibre insulation boards and also fixing wooden battens direct to wall (better than standard screws as the fixings are thermally broken). Have dolloped a bit of polyurethane d4 foaming wood glue in the hole for good measure before driving home and the battens are rock solid.