SHGD2015 - ESRI:115811

WKT

VERTCS["SHGD2015", 
	DATUM["St_Helena_Geodetic_Datum_2015", 
		SPHEROID["GRS_1980", 6378137.0, 298.257222101]], 
	PARAMETER["Vertical_Shift", 0.0], 
	PARAMETER["Direction", 1.0], 
	UNIT["Meter", 1.0]]

WKT2

VERTCRS["SHGD2015", 
	DATUM["St_Helena_Geodetic_Datum_2015", 
		ELLIPSOID["GRS_1980", 6378137.0, 298.257222101]], 
	CS[vertical, 1], 
	AXIS["Ellipsoidal height (h)", up, 
		LENGTHUNIT["Meter", 1.0]], 
	ID["Esri", "115811"]]

Data from @esri/proj-codes

{
  "wkid": 115811,
  "latestWkid": 115811,
  "macro": "PE_VCS_SHGD2015",
  "name": "SHGD2015",
  "wkt": "VERTCS[\"SHGD2015\",DATUM[\"St_Helena_Geodetic_Datum_2015\",SPHEROID[\"GRS_1980\",6378137.0,298.257222101]],PARAMETER[\"Vertical_Shift\",0.0],PARAMETER[\"Direction\",1.0],UNIT[\"Meter\",1.0]]",
  "wkt2": "VERTCRS[\"SHGD2015\",DATUM[\"St_Helena_Geodetic_Datum_2015\",ELLIPSOID[\"GRS_1980\",6378137.0,298.257222101]],CS[vertical,1],AXIS[\"Ellipsoidal height (h)\",up,LENGTHUNIT[\"Meter\",1.0]],ID[\"Esri\",\"115811\"]]",
  "description": "SHGD2015",
  "authority": "Esri",
  "version": "10.7.0",
  "deprecated": "no",
  "areaname": "St Helena - St Helena Island",
  "extent": {
    "slat": -16.08,
    "nlat": -15.85,
    "llon": -5.85,
    "rlon": -5.59
  }
}