The classic yellow duster. Sometimes our batches vary, so here's the latest: 41x52cm (but expect some shrinkage in the wash).
They are a household staple and a most excellent all round cleaning cloth. Use them wrung out and wet as well as for dry dusting. Just remember WASH THEM SEPARATELY until they are very, very old. The yellow will run and you won't be happy.
So why are they yellow? Here's what the BBC has to say