K-TUNED BRAKE BOOSTER LINE KITK TUNED Brake Booster Line Kit. Replace the ugly rubber brake booster hose on your K swap with our 8AN black braided line. This line not only looks great, but fits perfectly over your brake booster port, check valve and intake manifold port. This is the same type of braided hose that we use on our 6AN fuel line kits so it will give the engine bay a nice uniform look. The kit includes 3 feet of 8AN line and 4 black hose end covers with integrated clamp.