bumGenius 4.0 One-Size Diaper

bumGenius 4.0 One-Size Diaper Baby

bumGenius 4.0 One-Size Cloth Diaper


  • 3x3 snap down design adjusts the sizing to fit small, medium and large sizes (apx 8-35+ pounds).
  • Trim, snug and comfortable stretchy tabs provide a custom fit.
  • Waterproof insert stopper prevents leaking at the tummy.
  • Diapers include two inserts: a newborn insert (8-10 lbs) and a one-size insert for your older baby.
  • Wide slot opening makes it easy to stuff and remove insert.
  • Slot cover protects your baby from wetness.
  • Generous sizing accommodates larger babies.
  • Easily replaceable elastic keeps your diapers fresh. 

bumGenius 4.0 one size diaper adjustments

 bumGenius One-Size Cloth Diapers include a small, lightweight insert for newborns 8-10 pounds and a larger one-size insert for your growing baby. When your baby outgrows the newborn insert, it works as an overnight booster* or as extra absorbency for heavy wetters. (*larger babies usually need 2 large inserts overnight)




Cloth diapering has never been so easy! 

bumGenius 4.0 One-Size Cloth Diapers feature a stretchy butterfly closure system to provide a comfortable, trim fit. This makes cloth diapering as easy as using disposables. The simple design makes bumGenius 4.0 one-size cloth diapers perfect for care providers who might be resistant to cloth diapering (including daycares).  It's hard to deny the simplicity of this diaper!

Less Clutter

bumGenius 4.0 One-Size Cloth Diapers fit most babies from 8 to 35+ pounds. No more sorting by size or having to carry multiple diapers when going out. Three snap-downs on the front of the diaper allow you to easily adjust the size of the diaper as your baby grows. For newborns, fold down the insert stopper for an extra-small rise.

Only the Best for Your Baby

The soft, waterproof outer fabric keeps the diaper trim on your newborn and toddler. Soft, sueded inner fabric gently wicks moisture away from your baby's skin. Super stretchy, gentle leg and back elastic with rolled out casings keeps the yuk in and help to keep red marks away. The unique covered slot opening keeps your baby protected from moisture and keeps the insert neatly in place.

Care Instructions

Pre-wash cold. Wash hot (100F/40C) with an approved detergent.*  Extra rinse. No laundry additives. Line dry cover. Tumble dry insert. No fabric softeners. Optionally, use up to 1/4 cup bleach in the hot wash once per month.

*Approved detergents rinse well and are free of enzymes, brighteners, and fragrances.  These include Country Save, Planet, Allens, Mountain Green Free, Ecos Free, and bumGenius detergent.  Many of these detergents are available at grocery stores and health food stores such as Top Foods, QFC, Thriftway, PCC, Metropolitan Market, food co-ops, and Whole Foods.  You can also find these detergents online.  Using an approved detergent will keep your diapers fresh, clean, and in working order.  Use of non-approved detergents can coat diapers and void your warranty.  Always use only 1/2 the recommended amount of detergent for your type of machine and wash on a large load setting.  Add a wet towel if you use a front-load or HE machine to "trick" the machine into using more water.

New Colors Available!


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Wondering how the cost of cloth diapers compares to disposables, how to travel with cloth diapers, and what accessories are recommended?  Visit our FAQ page