The core of the SL patient monitoring system is known as the SL Command Module. It provides the power needed for basic physiologic parameters. A number of configurations are available, and providers can choose from these configurations depending on the needs of the patients or the medical unit. Also, it monitors 3 arrhythmia levels, analyzes and interprets ECG and provides reports, which may or may not include measurements. Providers also have the option to include the analysis of ST segment and event review. Varitrend 4 is likewise available, which reviews neonatal respiration, SpO2, and heart rate. Three technologies are available as well, namely Spacelabs, Nellcor OxiMax, and Masimo SET.