Sprinkler System Winterization Kit, Brass Fittings Designed To Fit On Either A 1/2" Riser Or On A Standard 3/4" Outdoor Hose Faucet, Used For Blowing Out An Irrigation System, Simply Remove A Sprinkler Head From The Line & Attach An Air Compressor Via The Adapter Fitting, Fits Most Brands Of Air Compressors, For Outdoor Irrigation Systems Only.