Will it fit a standard twin mattress?

Yes. It is cut for a twin at 38 by 75 inches, the common US twin size. Measure your mattress first if it is an odd size or very deep.

Is it really waterproof?

The cover has a waterproof backing to keep spills off the mattress. Wash and dry it as directed so the backing stays intact.

Yes, it is machine washable. Use a gentle cycle and avoid high heat to protect the cotton and the waterproof layer.

No. It is a thin protective cover, not a padded topper. Add a mattress pad if you want extra softness.

It is a rectangular cover rather than a deep-pocket fitted sheet, so it can shift. Tuck it under the mattress or use it beneath a fitted sheet.

One white twin mattress cover. No pillowcases or other pieces are included.

At The Home Depot, for $40.94, as of our latest check.

2 stores we checked sell it, including The Home Depot, Lowe's.

$40.94at The Home DepotChecked 19 h ago

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