Iron on and medium-thick volume lining. Thicker than H630. You can use Volume Lining H640 to reinforce bags, handles, belts, pencil cases, but also for extra lining of coats, sleeping bags, etc. Washable at 40°C and suitable for dry-cleaning. 
Lay the coated side on the wrong side of the fabric, cover with a damp cloth and press with the iron for about 15 seconds, do not iron. Iron on medium temperature, leave flat for another 30 minutes so that the volume lining sticks well to the fabric.