These liners are specifically shaped for use with mummy style sleeping bags. There is an integral hood, or pillow slot, which can be used to take a pillow or even your head for extra warmth or for protection against mossies and other biting insects. 

Unfolded they are a generous 90ins/230cm in length.  The widest point at the head is 34ins/85cm, tapering down to 22ins/56cm at the bottom.

The liner packs down to a space saving 4ins/10cm x 12.5cm and weighs in at 4.4oz/125g.