The polyurethane sheaths are designed with a special stress-relief hub sleeve to virtually eliminate the possibility of kinking at this junction. The polyurethane material resists permanent kinking in the sheath and soften in situ to deliver better indwelling characteristics. To aid insertion, the lock dilator is hand-fitted to the sheath for a smooth transition with minimum potential for peel-back. And the unique tricuspid design of the hemostasis valve permits easy catheter torquing and manipulation with minimum bleed-back, even with the spring-wire guide in place. The Introducer with Hemostasis Valve is of great benefit to the invasive cardiology and radiology procedures. And it is very use for and favorite in the OR, ER, Critical care, and Trauma units.