This isn’t the best place to get exposure, people here are more interested in your design process.
That being said I like the solid construction and am definitely a fan of thin wallets, I currently use a small leather sleeve. But I wouldn’t use this product because it would leave my Honda Civic key all alone. When it comes to keys and cards, the only way I’m going to change my current method will be with the advent of new technologies such as NFC chips for payments and keyless entry.