Vauxhall / Opel Unthreaded Plastic Nuts. Once removed they never hold as tight and so are best to replace.
10x Audi Plastic Nuts- Unthreaded 4mm diameter hole Engine Undertray Splashguard
Genuine GM 10x Exhaust Manifold Nuts Vauxhall Astra H Mk5 2004 to 2010 11082413
10x Vauxhall Bumper & Splash Guard Plastic Rivet Body Panel Retaining Trim Clips
VAUXHALL CORSA C FRONT REAR WHEEL ARCH TRIM CLIPS PLASTIC NUTS & METAL SCREWS
10x 5mm Plastic Rivet Clips for Trims, Wheel Arch Liner/Lining & Moudlings P/N - 51-16-1-881-149, 51161881149, 51160154946, 51-16-0-154-946
10x Ford Plastic Bonnet Insulation Panel Clips Fasteners- Mondeo Fiesta Transit
