St. Helena Tritan - ESRI:115812

WKT

VERTCS["St_Helena_Tritan", 
	DATUM["St_Helena_Tritan", 
		SPHEROID["WGS_1984", 6378137.0, 298.257223563]], 
	PARAMETER["Vertical_Shift", 0.0], 
	PARAMETER["Direction", 1.0], 
	UNIT["Meter", 1.0]]

WKT2

VERTCRS["St_Helena_Tritan", 
	DATUM["St_Helena_Tritan", 
		ELLIPSOID["WGS_1984", 6378137.0, 298.257223563]], 
	CS[vertical, 1], 
	AXIS["Ellipsoidal height (h)", up, 
		LENGTHUNIT["Meter", 1.0]], 
	ID["Esri", "115812"]]

Data from @esri/proj-codes

{
  "wkid": 115812,
  "latestWkid": 115812,
  "macro": "PE_VCS_ST_HELENA_TRITAN",
  "name": "St_Helena_Tritan",
  "wkt": "VERTCS[\"St_Helena_Tritan\",DATUM[\"St_Helena_Tritan\",SPHEROID[\"WGS_1984\",6378137.0,298.257223563]],PARAMETER[\"Vertical_Shift\",0.0],PARAMETER[\"Direction\",1.0],UNIT[\"Meter\",1.0]]",
  "wkt2": "VERTCRS[\"St_Helena_Tritan\",DATUM[\"St_Helena_Tritan\",ELLIPSOID[\"WGS_1984\",6378137.0,298.257223563]],CS[vertical,1],AXIS[\"Ellipsoidal height (h)\",up,LENGTHUNIT[\"Meter\",1.0]],ID[\"Esri\",\"115812\"]]",
  "description": "St. Helena Tritan",
  "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
  }
}