This is a black sealing plugs with 1/4 inch external thread, which internal thread is screwed into a 1/4 inch and is particularly flat. To temporarily or permanently unneeded openings can be closed. Only 5 mm high.
The addition of CF No.1 UV Acid Green improves performance and appearance of your water cooling and ensures your system for the future. No additional additives required. The product has been successfully tested with leading water cooling.