Thank you for your inquiry and for your interest in our 7 1/2" x 5/8" French Oak Unfinished Engineered wood floor. To answer your questions:

1. Yes, this floor can be glued directly to your concrete slab. We recommend a product called Mapei ECO 995, as we believe the moisture barrier protection it provides is second to none. We can definitely set you up with it if you choose to purchase through us.

2. You are correct, this unfinished floor has no "sealer" and would require some sort of finish on it to protect the floor. Many of our customers who want to preserve the natural/"raw" look of the floor use a product called Bona Traffic (available at most big box home stores) to achieve this end. Here are a couple of photos of this product & finish that a customer sent into us from a recent install to give you an idea of how that particular combination loos when finished:

Hope this info is helpful. We'd love the opportunity to partner with you on your next home flooring project. For a custom quote, feel free to reach out to us via the green "Contact Me" button located in the header of our Houzz profile. Let us know how we can help.