FEP Heat Shrink is used as a manufacturing aid to reflow the Pebax or Nylon jackets around the braid to bond with the underlying PTFE liner and ultimately form the catheter shaft. Zeus provides FEP Heat Shrink in custom ratios to maximize radial compression for optimized reflow and jacket-to-liner adhesion. The FEP fusing sleeve is then removed upon completion of the reflow process leaving behind a smooth void free surface.