The TYRX Anti-Bacterial Envelope is an FDA-cleared polypropylene mesh that is intended to securely hold a pacemaker pulse generator or defibrillator (ICD) in order to create a stable environment when implanted in the body. It contains the antimicrobial agents, rifampin and minocycline, which have been shown to reduce infection in an in vivo model of bacterial contamination following surgical implant of the generator or defibrillator.