Pre finished Hardwood flooring is factory stained and coated with a no wax finish of Polyurethane aluminum oxide for durability, or impregnated with Acrylic (depending on the brand selected) and is available as: 

1- Engineered Products (Plied construction consisting of 3-5 criss-cross plies) Engineered products are designed for glue-down installation, or in some cases a " Floating" installation over a thin Styrofoam pad over concrete or wood floors. Product thickness depends on the particular brand selected and ranges from 3/16" to 9/16". 

Engineered products are available in "Plank" form (3" wide strips) or "Strip" form (2 1/4" wide strips) both of which are available in standard board length, or random board length. The width of a plank does not affect performance in any way and is chosen by the consumer as a matter of aesthetic appeal. 

2- Solid products

Solid products in this category are also pre finished and coated with a no wax finish of Polyurethane or impregnated with Acrylic. Thickness range from 1/2" to 3/4". These products are designed for nail-down applications. The overall thickness (including the wood sub floor they are nailed onto may be up to 1 1/2" which is a deterrent to using this type of flooring in remodeling projects of existing homes unless the sub floor is recessed to accommodate such an installation). Otherwise, doors may have to be cut and adjoining rooms may be lower resulting in a hazardous condition. 

Custom Sand & finish Hardwood flooring 

Unfinished hardwood flooring is also available in Engineered products (Plied construction), or in solid form (1/2"- 3/4" wide) These products can be custom stained with your choice of color and coated with your preference of Polyurethane or wax finish. Some species of wood do not require a stain. When the wood is sealed or finished, it's natural color is highly desirable and is therefore not stained such as Chatoba Brazilian Cherry), Ebony (Black-colored), among many other species.