Hi Guys

Can you help? I'm sure this is a simple thing that I'm over looking.

My products are sold with weights of around 100g, I have changed the code to show g (using the overide system) I have installed the the Royal Mail add on and updated the postage rates.
Now I'm testing my cart and I go to buy a product that is 1 x 100g, when I go to check out it tells me:

Great Britain and Northern Ireland only : 5.000 kg(s) in 44 boxes £485.38.

Where is it getting this bizare info from?

Any help would be gratefully recieved.