People searching adult plastic backed diapers want a tape brief with a plastic outer, often after a cloth-like cover has wet clothes or sheets. A cloth-like outer is a different pack. Plastic pants worn over a brief are a different pack again. The waterproof back of a bed pad is a third thing, and it stays on the mattress. These notes do not include a brief whose listing says plastic-backed, so that phrase is not pinned to a price or a size. Nothing here was wear-tested.
Shoppers pick a plastic outer when they want fluid stopped before it reaches pants or bedding. Cloth-like is what many daytime briefs advertise when they talk about a quiet cover. The choice is which sentence the product page actually uses. A white brief in a photo does not settle it.

Read the outer, then the cut
Look in the title and the bullets for plastic-backed, poly backed, or a cloth-like outer. Tabs mean a tape brief. A pull-on can also be described either way, and it is still a different cut from tabs. If you need side tabs for changes, a pull-on with a plastic comment in a review is the wrong order.
One tab brief in these notes talks about cloth, not plastic. LivDry EnduraDry Max Adult Diapers with Tabs are a 16-pack in Medium, listed at $42.99 when this was written. The page says up to 12 hours. The bullets call the cloth latex-free and breathable. That is cloth wording. It is not a plastic-backed claim, and the pack should not be ordered as one. $42.99 divided by 16 is about $2.69 a brief. Medium still has to match a waist chart on that listing. These notes do not add an inch range the summary did not include. Check the price before you buy.

Cloth-like pull-ons, plastic pants, and bed pads
Prevail Daily Protective Underwear, unisex, maximum absorbency, Large, is 64 count in four packs of 16, listed at $53.67. Large is waists 44 to 58 inches. The page says day or overnight, with breathable zones plus aloe. Breathable zones are a comfort line, not the words plastic-backed. $53.67 divided by 64 is about 84 cents a pull-on. A pull-on at that price does not stand in for a plastic tape brief if tabs are what the change requires.
Plastic pants, the waterproof garment worn over a pad or brief, are not in these priced notes. Do not treat a bed pad’s back as the same purchase. A washable underpad here is 36 by 76 inches, with tuck-in sides, listed at $39.99, for king and California king beds. Another is 17 by 22 inches, listed at $9.65. Both protect a mattress. Neither is a brief you wear. Those bed sizes are sorted in Medline and washable bed pad sizes.
People who want a quiet afternoon often steer away from a plastic outer because it rustles under clothes. People who have already soaked through a cloth-like cover go looking for plastic words on purpose. Both are shopping reasons. Neither one shows up as a score on the listings in these notes. A review that says “plastic” is not the same as a title that says plastic-backed. Trust the title and the bullets, then look at the bag when it arrives.
Order the cut for the change you actually do. Tabs help when someone else fastens the brief, or when it should come off without a full undress. A pull-on helps when the wearer handles it alone. The Prevail Large at $53.67 is the pull-on with a printed waist in these notes. The LivDry Medium at $42.99 is the tab brief whose bullets talk about cloth. If you still need the plastic outer, keep looking. Do not relabel either of those packs to finish the search.
Order a plastic-backed tab brief only when the page says plastic-backed, or the same idea in plain words, and the waist matches. If the bullets say cloth, breathable, or cloth-like, you are on the other outer. The LivDry 16-pack at $42.99 falls in that second group because of the cloth wording, not because of a lab comparison. Recheck the listing. Wording on a page and the bag that arrives can drift, and a review that says plastic is not the product title.