Narrower inner diameter increases flow resistance and reduces foaming at high dispensing pressures or in shorter serving lines. This is the same diameter tubing used in our Foam Free Tubing Kits. Flow Resistance is 3 psi/foot.We recommend the use of 3/16 Barbed Swivel Nuts (K123) for easy threaded connections to MFL draft equipment such as a CO2Regulator,gas distributormanifolds, and Soda Keg Disconnects.Sold in pre-cut lengths: 3, 10, 20, or 30 feet