NAD83(CSRS)v8 - ESRI:115931

WKT

VERTCS["NAD83(CSRS)v8", 
	DATUM["North_American_Datum_of_1983_(CSRS)_version_8", 
		SPHEROID["GRS_1980", 6378137.0, 298.257222101]], 
	PARAMETER["Vertical_Shift", 0.0], 
	PARAMETER["Direction", 1.0], 
	UNIT["Meter", 1.0]]

WKT2

VERTCRS["NAD83(CSRS)v8", 
	DATUM["North_American_Datum_of_1983_(CSRS)_version_8", 
		ELLIPSOID["GRS_1980", 6378137.0, 298.257222101], 
		ANCHOREPOCH[2010.0]], 
	CS[vertical, 1], 
	AXIS["Ellipsoidal height (h)", up, 
		LENGTHUNIT["Meter", 1.0]], 
	ID["Esri", "115931"]]

Data from @esri/proj-codes

{
  "wkid": 115931,
  "latestWkid": 115931,
  "macro": "PE_VCS_NAD_1983_CSRS_V8",
  "name": "NAD83(CSRS)v8",
  "wkt": "VERTCS[\"NAD83(CSRS)v8\",DATUM[\"North_American_Datum_of_1983_(CSRS)_version_8\",SPHEROID[\"GRS_1980\",6378137.0,298.257222101]],PARAMETER[\"Vertical_Shift\",0.0],PARAMETER[\"Direction\",1.0],UNIT[\"Meter\",1.0]]",
  "wkt2": "VERTCRS[\"NAD83(CSRS)v8\",DATUM[\"North_American_Datum_of_1983_(CSRS)_version_8\",ELLIPSOID[\"GRS_1980\",6378137.0,298.257222101],ANCHOREPOCH[2010.0]],CS[vertical,1],AXIS[\"Ellipsoidal height (h)\",up,LENGTHUNIT[\"Meter\",1.0]],ID[\"Esri\",\"115931\"]]",
  "description": "NAD83(CSRS)v8",
  "authority": "Esri",
  "version": "13.2.0",
  "deprecated": "no",
  "areaname": "Canada",
  "extent": {
    "slat": 38.21,
    "nlat": 86.46,
    "llon": -141.01,
    "rlon": -40.73
  }
}