GRAV Labs 4' Hammer Bubbler (10 Pack) - Assorted Colors - 32mm Glass A pack that's sure to bring in the cash. The GRAV� Hammer Bubbler is 4" tall and made on 32mm tubing. Its fission downstem diffuses smoke through water, and its feet stabilize the bubbler between uses. No accessories are necessary for using this bubbler, and it functions best with approximately 0.5" of water. Length Height : 7" Use With : Flower Carb : On The Left Designed By : Dave Daily