SDT BRAKES We manufacture steel brake hoses improve braking response and performance by 25%. Unexpandable and inextensible tubing kit that improves the feel and reaction speed of the brake system. Prepared to replace the originals. Composition: Inner tube of PTFE (Teflon) type 62, outer braided of AISI 304L stainless steel and coated with black PVC. Its main difference is its composition of the highest quality.