Safety Liner for deep fill softside waterbed. Perfect for softside waterbeds that 6, 7or 8" in depth. If you have a softside waterbed and you are replacing the internals of your mattress then be sure to replace the safety liner. Old liners will tend to get cracks from age and heating systems. It is a low cost item that could save the day if you had a leak in you water bladder. If you have any questions contact us and we will be more than happy to help. Thank-you for looking at our products and be sure to check our our Mattress Covers Amazon store for our large selection of waterbed products.