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HAHA.. Oops.. They are door sills not window sills, window sills would be pointless and kind of stupid... Well anyways they would look pretty sick on the outside of your doors, especially if you have chrome window trim that outlines the window sills.

They go on where the bottom of the door meets the car.

By looking at them, they look like they'd fit sedan but not the coupe or maybe vice versa since sedans and coupe have different sized sills.
JDM coupes have the authentic ones which can be put on our existing sills with some modifications. Refer to this thread to see how it can be done.

Keith's JDM Doorsill DIY