The Utillian Glass Bubbler is a great addition to your growing Utillian arsenal. It's compatible with UTILLIAN 2, UTILLIAN 5, UTILLIAN 420, UTILLIAN 421, and UTILLIAN 620 our multiple vaporizers and wax pens. The Utillian Glass bubbler is designed to cool your vapor for a smoother draw. Makes the product taste better and easy to put it together.