BIAB stands for Builder in a Bottle.
It is a thicker strengthening gel used on natural nails to help them grow longer and stronger without extensions. BIAB is a builder gel that comes in a bottle with a brush, similar to gel polish — but much thicker and stronger.
It is used to:
* Thicker than gel polish
* Softer than hard gel or acrylic
* Flexible so it moves with the natural nail
* Needs infills every 2–3 weeks instead of full removal
