The Piston Gravity Bong transforms tradition with its piston-shaped design and first-of-its-kind disc percolation system that produces smooth, powerful hits. Handmade from premium borosilicate glass, this piece features a removable 14mm slide and gravity slide function for a modern, mechanical-inspired smoking experience. Material: 100% Borosilicate Glass Joint: 14mm Dimensions: 8.5" x 3.5" What’s in the box: 1x Piston Gravity Bong