These hub spacers are a great way to bring your rear wheels a bit wider without using the unsightly wheel spacer most people run. These are not camber shims they are flat and not tapered. 
They are made from laser cut 1/2in steel. The 1in kit will be 4 steel spacers wheras the 1/2in kit will be only 2 spacers. 
Your kit will come with spacers and new longer bolts. 1 kit=1 Car