Belge 1950 (Brussels) - EPSG:4809

WKT

GEOGCS["GCS_Belge_1950_Brussels", 
	DATUM["D_Belge_1950", 
		SPHEROID["International_1924", 6378388.0, 297.0]], 
	PRIMEM["Brussels", 4.367975], 
	UNIT["Degree", 0.0174532925199433]]

WKT2

GEOGCRS["GCS_Belge_1950_Brussels", 
	DATUM["D_Belge_1950", 
		ELLIPSOID["International_1924", 6378388.0, 297.0]], 
	PRIMEM["Brussels", 4.367975, 
		ANGLEUNIT["Degree", 0.0174532925199433]], 
	CS[ellipsoidal, 2], 
	AXIS["Latitude (lat)", north, 
		ORDER[1]], 
	AXIS["Longitude (lon)", east, 
		ORDER[2]], 
	ANGLEUNIT["Degree", 0.0174532925199433], 
	ID["EPSG", "4809"]]

Data from @esri/proj-codes

{
  "wkid": 4809,
  "latestWkid": 4809,
  "macro": "PE_GCS_BELGE_1950_BRUSSELS",
  "name": "GCS_Belge_1950_Brussels",
  "wkt": "GEOGCS[\"GCS_Belge_1950_Brussels\",DATUM[\"D_Belge_1950\",SPHEROID[\"International_1924\",6378388.0,297.0]],PRIMEM[\"Brussels\",4.367975],UNIT[\"Degree\",0.0174532925199433]]",
  "wkt2": "GEOGCRS[\"GCS_Belge_1950_Brussels\",DATUM[\"D_Belge_1950\",ELLIPSOID[\"International_1924\",6378388.0,297.0]],PRIMEM[\"Brussels\",4.367975,ANGLEUNIT[\"Degree\",0.0174532925199433]],CS[ellipsoidal,2],AXIS[\"Latitude (lat)\",north,ORDER[1]],AXIS[\"Longitude (lon)\",east,ORDER[2]],ANGLEUNIT[\"Degree\",0.0174532925199433],ID[\"EPSG\",\"4809\"]]",
  "description": "Belge 1950 (Brussels)",
  "authority": "EPSG",
  "version": "4.5(3.0.1)",
  "deprecated": "no",
  "areaname": "Belgium - onshore",
  "extent": {
    "slat": 49.5,
    "nlat": 51.51,
    "llon": 2.5,
    "rlon": 6.4
  }
}