MURADIN Men's Wallet Tactical Bifold Wallet for Men Metal RFID Blocking Aluminum Money Card Holder Gift for Men

Q: How many cards fit into the aluminum slider?

You can fit 7 cards in the card slot and two cards on the exterior wallet slots. Plus an ID slot that can hold ID plus one card behind it. So 10 total. This is for credit cards no place to put cash. Good for me because I never carry cash.

Q: Is the ID window a full window? (Most wallets have a hole in the middle.)

There is no plastic covering the ID. It's just the "leather" that surrounds the edges of the ID that hold it in. With that said, the ID holds firm. I've never had an issue with it falling out.