Independently lab tested and certified bed bug entry, escape and bite proof * Surrounds and protects the crib mattress on all 6-sides against allergens, dust mites, bed bugs, bacteria, fluids, perspiration and urine (10-year warranty and machine washable) * Exclusive Micro-Zipper technology prevents all stages of bed bugs from passing through the zippers teeth * 360 Secure zipper closing feature prevents accidental openings by sealing the end zipper traveler with a Velcro flap * Premium cotton terry surface material with breathable hypoallergenic membrane backing keeps the mattress cool and noiseless while blocking dust mites and other allergens.