Locking Wheel Nut Kit for Land Rover Discovery 1 Alloy Wheels Silver mirror cover 3x Black Anodised Aluminium cargo 3x Black Anodised Aluminium cargo tracks (50mm wide In theory you need an M8 rivnut fitting tool to fit these captive nuts but if you drill a hole and ensure the rivnuts are a tight fit and can't spin then in practice we find we can hammer the rivuts into the hole and then fit the step and the rivnut will tighten inside the chassis as you tighten the bolts The sloped ends on these nuts helps with location into the wheel holes but may also help to secure a spare steel wheel ('steel wheel' nuts are sloped) The load face is fitted with a washer that is free to spin but is crimped so that it cannot slide off the nut (this washer ensures you can apply maximum force on the wheels)