Lighten the load a little and take paper laundry soap with you when you travel.
The little plastic case measures only 4.5cm x 6.5cm and contains 30 sheets of laundry soap. Simply remove a sheet from the pack, add water and lather away. Perfect for washing socks and underwear.
The paper laundry soap pack doesn't contain liquid, so can be carried in hand luggage on flights and weighs very little.