These fasteners are for holding on the engine undertray - that is the bottom cover under the car that protects the engine form underneath from dirt and water etc. NOT made from cheap inferior materials.
Rover 75, MG ZT, ZT-T 1999-2005 Manual / Auto Engine Cooling Radiator GRD1055
Genuine MG Rover - 75 / MG ZT - Coolant Hose Pipe Assembly To Pump - PEH101300
Rover 75 / MG ZT Air Conditioning Trinary Switch - JTB000010 Genuine MG
1999 - 2007 Rover 75 & MG ZT Power Steering Pipe Hose (QEH000740)
Rover 75 & MG ZT 1.8 Turbo Power Steering Reservoir (QEH000680 & QEH000780)
Under Engine Cover Undertray Rust Splash Guard for Rover 75 & MG ZT