K STRIP (K) is the top of the line, sound, structural grade similar to a narrow Premium Frame. Each board contains one rail with a Minimum Cuttings: 4 1/4 inch to 4 3/4 inch wide by 7 feet long or longer. This product is also popular where a knotty appearance is desired. 
Widths: 4 1/4 inch to 4 3/4 inch only
Lengths: 7 feet minimum

Minimum Size Cuttings: Minimum of one cutting 4 1/4 inch to 4 3/4 inch by 7 foot sound cutting as described in Sound Cutting.

Face knot size is limited to 1/2 inch unsound and, 1inch sound

Each board will yield not less than 83 1/3 percent. The reverse side will grade to Frame or better.

Wane: This board shall be free of wane

Side Bend: is not allowed