@NatB
I find them quite trim, and Percy has never had nappy rash with them.
I used them in boosted when he was tiny (worked out a similar size on the bum to a muslin with a bat fold), the with a thin booster. He's now 12lb and I use with the flannel boosters; the size is comparable to a folded Terry square, much smaller than fitted ll or similar, and with a wrap looks trimmer than a pocket.
His big is your baby?
Are you tucking the gusset in to make it narrow enough so as not to rub?
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