Nylon Spiral Self Tapping Wall Anchor 12mm x 70mm Plastic Drywall Plasterboard Fastener with Conical Drill Tip for Aerated Concrete Product Description The 12mm x 70mm Nylon Spiral Self Tapping Wall Anchor is a premium plastic fastening solution engineered for aerated concrete / gypsum block applications. Featuring a sharp conical drill tip and helical spiral body structure, this self-tapping anchor can be screwed directly into the wall surface without pre-drilling a pilot