Saf-T-Intima Closed IV Catheter System Incorporates preattached extension tubing to help support reduction in blood exposure. Closed system: Preattached extension tubing offers a closed system to minimize blood exposure during catheter insertion. Removable adapter: A removable PRN adapter allows the use of an ISO-compliant needleless connector. BD Vialon biomaterial: The system is constructed with BD Vialon biomaterial, a proprietary catheter material that softens in the vein. 22G x 3/4 inch PRN Needle 25 per box.