Does it fit a Twin XL mattress?

Yes. It is sized for Twin XL beds at 38 by 80 inches, with a fitted skirt.

Is it actually waterproof?

Yes. Purple lists it as waterproof, so spills should not reach the mattress.

It adds a thin layer. Most owners say the mattress feel is largely unchanged.

Yes. It is a standard fitted protector and fits any Twin XL mattress of the same size.

The best new price seen is $122.82 at Lowe's as of November 7, 2026. Watch for holiday sales, when protectors are often discounted.

At Lowe's, for $122.82, as of our latest check.

$122.82at Lowe'sObserved at 7:10 AM

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