4 important and easy to forget items to bring during travel

When we go for a long trip, we need to pack a lot of things, and sometimes left out some small and little useful items behind. Even though we can buy these items during the trip, but it is economically not worth (first you might already have it at home, second you can use that kind of money to buy other things):

1. Power extension, especially you share your room with others. Hotel room normally provide limited power socket, and may be you and your partner need to charge up notebook, hand phone and camera in the same time.
   
2. Small travel bag, useful when your luggage is overload with things you bought during the trip.
   
3. Charger, if you want to make sure you can use your electrical devices along the whole trip.
   
4. Slipper, so that you won't need to wear shoes for only go out to buy a pack of snack.