Swaddle Sack for Babies: Useful?

Dear community,
Is a swaddle sack for babies a good idea, or not really? How is it different from a baby sleep sack?

I’d say: It depends on the baby.
Not all babies like to be swaddled tightly.

I never used one myself.

My three kids didn’t like being swaddled either—they screamed their heads off when I tried it once, so I gave up on it, and they still slept through the night just fine.

Love, Inge

Good morning,
The little baby leg bags are often mistakenly referred to as swaddling bags. That’s just how the term has become established.
In fact, swaddling bags aren’t “bags” at all, but special swaddling blankets designed to wrap a baby very tightly so that the baby doesn’t wake itself up with the sudden, jerky movements typical of infants (often involving the arms).
It also gives the baby the feeling of the snugness and security of the womb again. However, you “have to” start using them soon after birth. (But please have someone who knows this well show you how! A lot can be done wrong!)
Everything else is a baby leg bag, in which babies—ideally with otherwise bare legs—have plenty of freedom of movement and can feel their own bodies.
They’re often used as a substitute for baby sleeping bags.

Best