PROJCRS["Sister Islands National Grid 1961",
    BASEGEOGCRS["SIGD61",
        DATUM["Sister Islands Geodetic Datum 1961",
            ELLIPSOID["Clarke 1866",6378206.4,294.978698213898,
                LENGTHUNIT["metre",1]]],
        PRIMEM["Greenwich",0,
            ANGLEUNIT["degree",0.0174532925199433]],
        ID["EPSG",4726]],
    CONVERSION["Cayman Islands TM (ft)",
        METHOD["Transverse Mercator",
            ID["EPSG",9807]],
        PARAMETER["Latitude of natural origin",0,
            ANGLEUNIT["degree",0.0174532925199433],
            ID["EPSG",8801]],
        PARAMETER["Longitude of natural origin",-81,
            ANGLEUNIT["degree",0.0174532925199433],
            ID["EPSG",8802]],
        PARAMETER["Scale factor at natural origin",0.9996,
            SCALEUNIT["unity",1],
            ID["EPSG",8805]],
        PARAMETER["False easting",1640419.9475,
            LENGTHUNIT["foot",0.3048],
            ID["EPSG",8806]],
        PARAMETER["False northing",0,
            LENGTHUNIT["foot",0.3048],
            ID["EPSG",8807]]],
    CS[Cartesian,2],
        AXIS["(E)",east,
            ORDER[1],
            LENGTHUNIT["foot",0.3048]],
        AXIS["(N)",north,
            ORDER[2],
            LENGTHUNIT["foot",0.3048]],
    USAGE[
        SCOPE["Cadastre, engineering survey, topographic mapping."],
        AREA["Cayman Islands - Little Cayman and Cayman Brac."],
        BBOX[19.63,-80.14,19.78,-79.69]],
    ID["EPSG",6129]]