14mm Glass Ground Joint Female Cap Plug - Glass Stopper Cap for Concentrate RIG Cleaning (14mm Cap) Go to amazon.com Related posts Top 10 best concentrate rig glass: Which is the best one in 2022? Feature14mm Glass Ground Joint Female Cap Plug - Glass Stopper Cap for Concentrate RIG Cleaning (14mm Cap) Description14mm Glass Ground Joint Female Cap Plug - Glass Stopper Cap for Concentrate RIG Cleaning (14mm Cap)