C&D braze-on self-piercing copper saddle valve for 3/8" tube CD5538. Package of 6. The First and Best Braze-On, Self Piercing Copper Saddle Valve. It is Widely Used and Easily Installed on a Charged Line. After Brazing the Saddle Portion Onto Line, the Steel Pin wit Calve Core Penetrates the Line and is Locked Into Place Simply By Tightening the Cap