Screws
If you have holes in your bumper, any of the screw kits are they way to go. If you don't have holes in your bumper, you will need to drill them and add a screw kit to the order.

Import Vs. Domestic Locking Screws
Import screw kits use metric size screws and are meant for foreign cars such as Audi, BMW, Mercedes and VW.
Domestic screw kits use standard size screws and are meant for US cars such as Chevy, Ford and Dodge.