Double compression fittings are manufactured for low pressure applications and have fair vibration resistance. Assembly requires no flaring, allowing quick installation and removal of fittings. To assemble, insert tubing through nut into body of the fitting, as far as shoulder permits. Hand tighten as far as possible, then tighten with wrench 1 1/2 turns. The sleeve end of the nut is wedged in the tapered seat of the body, biting into the tubing, forming a liquid tight seal.