Carbon Fiber Stock Kit includes the Butt Plate and Chassis Connection Sleeve (6061T6 Aluminum), Carbon Fiber Tube (19.5″ long), and Nylon12 end plug. These stocks fits all current Crazy Ivan Chassis and those sold since 1/1/2020, but do not fit other chassis on the market or ARs. As an option you can add a Foam Pad/Riser or Adjustable Nylon12 Riser. The Foam Pads/Risers are smooth-skin NPVC, are 6″ long, and come in two thicknesses (0.265 and 0.450). The Nylon12 Riser can be positioned anywhere along the carbon fiber tube and is adjustable from 0.5 to 2.75 inches. The tubes are available in black, camo, and a variety of colors. The tube comes uncut so it can be custom cut to any Length of Pull (as measured from trigger to butt plate). For reference, most factory rifles have a LOP of approximately 13.5 inches. When ordering, please select Color and if you want it cut. Please enter Length of Pull if cut is selected. The tubing can be easily cut with a fine-tooth hacksaw, bandsaw, or similar. Detailed instructions are included.