Grav Labs slides are the perfect addition to any water pipe. Whether you're looking to replace your broken Grav bowl or add a nice size/shape bowl to your current set up, these replacement bowls are perfect. It's no wonder why they're one of our top selling replacement bowls. The funnel style bowl holds about a gram of ground tobacco! It is available in your choice of 14mm or 18mm sizes. The bowl features a single Maria ring which makes this slide easy to hold and remove in a snap.