SRVN16 height - EPSG:9255

WKT

VERTCS["SRVN16_height", 
	VDATUM["Sistema_de_Referencia_Vertical_Nacional_2016"], 
	PARAMETER["Vertical_Shift", 0.0], 
	PARAMETER["Direction", 1.0], 
	UNIT["Meter", 1.0]]

WKT2

VERTCRS["SRVN16_height", 
	VDATUM["Sistema_de_Referencia_Vertical_Nacional_2016"], 
	CS[vertical, 1], 
	AXIS["Gravity-related height (H)", up, 
		LENGTHUNIT["Meter", 1.0]], 
	ID["EPSG", "9255"]]

Data from @esri/proj-codes

{
  "wkid": 9255,
  "latestWkid": 9255,
  "macro": "PE_VCS_SRVN16_HT",
  "name": "SRVN16_height",
  "wkt": "VERTCS[\"SRVN16_height\",VDATUM[\"Sistema_de_Referencia_Vertical_Nacional_2016\"],PARAMETER[\"Vertical_Shift\",0.0],PARAMETER[\"Direction\",1.0],UNIT[\"Meter\",1.0]]",
  "wkt2": "VERTCRS[\"SRVN16_height\",VDATUM[\"Sistema_de_Referencia_Vertical_Nacional_2016\"],CS[vertical,1],AXIS[\"Gravity-related height (H)\",up,LENGTHUNIT[\"Meter\",1.0]],ID[\"EPSG\",\"9255\"]]",
  "description": "SRVN16 height",
  "authority": "EPSG",
  "version": "9.8.5(12.6.0)",
  "deprecated": "no",
  "areaname": "Argentina - onshore",
  "extent": {
    "slat": -55.11,
    "nlat": -21.78,
    "llon": -73.59,
    "rlon": -53.65
  }
}