WGS 1984 (G873) - ESRI:115820

WKT

VERTCS["WGS_1984_(G873)", 
	DATUM["World_Geodetic_System_1984_(G873)", 
		SPHEROID["WGS_1984", 6378137.0, 298.257223563]], 
	PARAMETER["Vertical_Shift", 0.0], 
	PARAMETER["Direction", 1.0], 
	UNIT["Meter", 1.0]]

WKT2

VERTCRS["WGS_1984_(G873)", 
	DYNAMIC[
		FRAMEEPOCH[1995.5], 
		MODEL["NNR-NUVEL1A"]], 
	DATUM["World_Geodetic_System_1984_(G873)", 
		ELLIPSOID["WGS_1984", 6378137.0, 298.257223563]], 
	CS[vertical, 1], 
	AXIS["Ellipsoidal height (h)", up, 
		LENGTHUNIT["Meter", 1.0]], 
	ID["Esri", "115820"]]

Data from @esri/proj-codes

{
  "wkid": 115820,
  "latestWkid": 115820,
  "macro": "PE_VCS_WGS_1984_G873",
  "name": "WGS_1984_(G873)",
  "wkt": "VERTCS[\"WGS_1984_(G873)\",DATUM[\"World_Geodetic_System_1984_(G873)\",SPHEROID[\"WGS_1984\",6378137.0,298.257223563]],PARAMETER[\"Vertical_Shift\",0.0],PARAMETER[\"Direction\",1.0],UNIT[\"Meter\",1.0]]",
  "wkt2": "VERTCRS[\"WGS_1984_(G873)\",DYNAMIC[FRAMEEPOCH[1995.5],MODEL[\"NNR-NUVEL1A\"]],DATUM[\"World_Geodetic_System_1984_(G873)\",ELLIPSOID[\"WGS_1984\",6378137.0,298.257223563]],CS[vertical,1],AXIS[\"Ellipsoidal height (h)\",up,LENGTHUNIT[\"Meter\",1.0]],ID[\"Esri\",\"115820\"]]",
  "description": "WGS 1984 (G873)",
  "authority": "Esri",
  "version": "10.7.0",
  "deprecated": "no",
  "areaname": "World",
  "extent": {
    "slat": -90,
    "nlat": 90,
    "llon": -180,
    "rlon": 180
  }
}