These can be machine washed in 40 degrees Celsius if necessary. Hang dry. Once in a while the top fabric should be treated with water repellent spray if you wish to keep it more breathable.
Sizes in simple S, M, L form, in the brackets you can see the comparable US Army size, which seem to correspond rather well. Explanation for most sizes can be found in the US trouser size chart. In Belgish, X-Large is "EL" and X-Large Long is "ELL". The sizes grow both lengthwise and widthwise when going up the size table. These are roomy enough to accommodate field trousers and liner trousers underneath.
Unissued, just stored for a while.
Stephen H.
Bryan P.
Steffen R.