Hickory is the hardest commonly used domestic wood for flooring… 50% harder than Red Oak. This flooring has a subtle hand-scraped stained 4mm wear layer with a hand-crafted microbevel. It’s suitable for above and below grade installations but not for radiant heat. It can be nailed, glued or floated. Natural variations and occasional knots are allowed in this grade. Structure and finish have a limited lifetime residential warranty.