Sentec, V-Sign Sensor 2 (REF VS-A/P/N), Reusable / Nonsterile / Waterproof, SenTec AG, CH-4106, Therwil, Switzerland. The SenTec Digital Monitoring System (SDMS) is used for continuous and non-invasive monitoring of transcutaneous carbon dioxide tension (tcPCO2), oxygen saturation (SpO2), || and pulse rate (PR).