MSL UK and Ireland VORF08 depth - EPSG:10150

WKT

VERTCS["MSL_UK_Ireland_VORF08_depth", 
	VDATUM["Mean_Sea_Level_UK_Ireland_VORF08"], 
	PARAMETER["Vertical_Shift", 0.0], 
	PARAMETER["Direction", -1.0], 
	UNIT["Meter", 1.0]]

WKT2

VERTCRS["MSL_UK_Ireland_VORF08_depth", 
	VDATUM["Mean_Sea_Level_UK_Ireland_VORF08"], 
	CS[vertical, 1], 
	AXIS["Gravity-related height (H)", down, 
		LENGTHUNIT["Meter", 1.0]], 
	ID["EPSG", "10150"]]

Data from @esri/proj-codes

{
  "wkid": 10150,
  "latestWkid": 10150,
  "macro": "PE_VCS_MSL_UK_IRELAND_VORF08_DEPTH",
  "name": "MSL_UK_Ireland_VORF08_depth",
  "wkt": "VERTCS[\"MSL_UK_Ireland_VORF08_depth\",VDATUM[\"Mean_Sea_Level_UK_Ireland_VORF08\"],PARAMETER[\"Vertical_Shift\",0.0],PARAMETER[\"Direction\",-1.0],UNIT[\"Meter\",1.0]]",
  "wkt2": "VERTCRS[\"MSL_UK_Ireland_VORF08_depth\",VDATUM[\"Mean_Sea_Level_UK_Ireland_VORF08\"],CS[vertical,1],AXIS[\"Gravity-related height (H)\",down,LENGTHUNIT[\"Meter\",1.0]],ID[\"EPSG\",\"10150\"]]",
  "description": "MSL UK and Ireland VORF08 depth",
  "authority": "EPSG",
  "version": "10.077(13.2.0)",
  "deprecated": "no",
  "areaname": "Europe - Ireland and UK offshore",
  "extent": {
    "slat": 47.42,
    "nlat": 63.89,
    "llon": -16.1,
    "rlon": 3.4
  }
}