Hydro Flow 1/2 Inch Compression Coupler, Bag of 10 Hydro Flow 1/2" Compression Fittings allows for a tight fit to 1/2" poly tubing, perfect for outdoor or indoor applications Made of plastic Sold in case quantities only Hydro Flow 1/2" Compression Fittings allows for a tight fit to 1/2" poly tubing, perfect for outdoor or indoor applications Made of plastic These fittings are easy to use and reliable