If you do a search for 'nose weight' you may find the answer in an earlier thread but it is in any case irrelevant.

The important figures are the maximum nose weights of a) your caravan and b) your tow bar. For maximum towing stability you should aim to achieve a nose weight as near as possible to the lower of the two figures.

Sorry if this comes over as advising elderly female relativeson the correct method to be adopted when sucking ova, but it may be of help to people new to caravanning.