Bendable Bubble wall 120cm 47.2"- Air Stone curtain tube pump 4/6mm air tubing Permeable Flexible Air Stones are a great way to aerate your growing system. The flexible stones bend into any shape you need to deliver air where you need it most, they also create less back pressure than traditional air stones, which reduces damage to your pump. This product is 100% brand new without retail packaging. Measures approximately: SIZE 120cm (47.2") and 0.85mm in diameter.. for 4/6mm air tube.