These are definitely not Laura Ashley standards, you get what you pay for. However these do exactly what they say and work well as black out curtains. Easy to wipe dust from. If you want them perfect you will need to give them an iron. Good little set of curtains.
Light can't go through it, indeed - but the back of it is white and reflective, so all the light comes in anyway through the sides. It would be better if they added a light absorbant layer on the back.