On all our sleeping bags, we have stated the optimal length and optimal width per person. You are not given the actual length and width of the sleeping bag, but the optimal height/width of the person who will use the sleeping bag. The sleeping bag should not be too tight so that you press the insulation together, then bullet points will occur. If the sleeping bag is too long or too large, it will require a lot of energy from you to heat the extra air inside the sleeping bag. The sleeping bag will therefore feel colder.