Woot offers Simply Soft Bed Bug Mattress Protector, Twin XL, White (SS-Bedbug-TWINXL) for $19.99 (orig. $26.25) + free shipping with Prime.

Product Description:

Safeguard your investment and protect your health with the Simply Soft total mattress Encasement. Lab tested and certified for 100% worry-free protection. The Simply Soft mattress Encasement is designed with your comfort in mind without sacrificing protection. Our dual-layer design creates a moisture and organism proof barrier for your mattress, while you enjoy the cool comfort of 100% breathable and soft microfiber fabric. And don't worry, it doesn't make the crinkle noise, we've worked that out too.
 

• Microfiber
• Imported
• Independently Lab Tested-Stretchable Fabric Mattress Encasement Makes Installation A Breeze
• Protects The Mattress On All 6-Sides
• 100% Waterproof and Breathable, Ultra-Soft Microfiber Material Keeps You Cozy While You Sleep
• Our Dual-Layer Design Creates A Moisture and Organism Proof Barrier For Your Mattress

Thanks Maggie