List<CIMClassBreak> listClassBreaks = new List<CIMClassBreak>
{
    new CIMClassBreak
    {
        Symbol = SymbolFactory.Instance.ConstructPointSymbol(ColorFactory.Instance.RedRGB, 12).MakeSymbolReference(),
        UpperBound = -4124.13
    },
    new CIMClassBreak
    {
        Symbol = SymbolFactory.Instance.ConstructPointSymbol(ColorFactory.Instance.GreenRGB, 12).MakeSymbolReference(),
        UpperBound = -3389.27
    },
    new CIMClassBreak
    {
        Symbol = SymbolFactory.Instance.ConstructPointSymbol(ColorFactory.Instance.BlueRGB, 12).MakeSymbolReference(),
        UpperBound = -2321.95
    },
    new CIMClassBreak
    {
        Symbol = SymbolFactory.Instance.ConstructPointSymbol(ColorFactory.Instance.GreyRGB, 12).MakeSymbolReference(),
        UpperBound = -1566.68
    },
    new CIMClassBreak
    {
        Symbol = SymbolFactory.Instance.ConstructPointSymbol(ColorFactory.Instance.WhiteRGB, 12).MakeSymbolReference(),
        UpperBound = -38.51
    }
};‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

CIMClassBreaksRenderer cimClassBreakRenderer = new CIMClassBreaksRenderer
{
    ClassBreakType = ClassBreakType.GraduatedColor,
    ClassificationMethod = ClassificationMethod.Manual,
    //Field = SDKHelpers.GetNumericField(featureLayer),
    Field = "NewPressure",
    Breaks = listClassBreaks.ToArray()
};
featureLayer?.SetRenderer(cimClassBreakRenderer);‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍