Super King Allerzip Smooth mattress encasement provides total mattress protection. It is stain proof, waterproof and prohibits the growth of bacteria. It is also bed bug entry and escape proof. Zip links are available. Total Encasement Solution Waterproof Miracle Membrane on all six sides. Allergen barrier on all six sides. Air vapour porous. Test washed 200 times.BugLock / Secure Seal / date coded.Colour coded size labels. Double stitched commercial grade French seams.Three sided micro zipper and allergen flap