All four that I bought (2 sets of 2) seems to be working just fine. This is the first set that we didn't buy that didn't zip around the entire mattress.
Twin Size Zippered Mattress Protector Encasement - Premium Terry Absorbent Cover With Six-Sided Waterproof Protection - Quiet, Breathable, And Fully Washable
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Protect And Comfort Your Mattress With FeelAtHome 100% Waterproof Fitted Cover For Twin Size - Soft & Noiseless Cotton Terry Fabric
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Twin Mattress Protector Waterproof Soft & Breathable Terry, Noiseless Mattress Cover Fits Up -14'' Depth, Skin-Friendly Machine Wash Mattress Protector
29 Review
Waterproof Twin XL Mattress Encasement With Zippered 6-Sided Cover, PlushDeluxe Premium Quality, And Cotton Terry Surface (Fits 12-15 Inches H)
14 Review
Black 2-Pack Of Vivere EFHTS Accessories For Hammocks
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Small Seagrass Belly Basket By BlueMake - Perfect For Storage, Plant Pot, Laundry, Picnic & Grocery!
41 Review
LOFTEK LED Dimmable Floating Pool Lights Ball, 16-Inch Cordless Night Light With Remote, 16 RGB Colors & 4 Modes, Rechargeable & Waterproof, Perfect For Indoor/Outdoor, Exhibition Decor, 1-Pack
38 Review
Stylish Solid Stainless Steel Metal Strap Replacement Band For Fitbit Versa 2, Versa Lite, Versa SE - Compatible With Men And Women - Black
31 Review