This product is a part of the EK Classic Product Line that is characterized by minimalistic and clean design while maintaining class-leading performance. Less talk, more cooling!EK-STC Classic 10/13 (Soft Tubing Compression) Fittings are 10/13 soft-tube compression fittings designed for use with flexible soft tubing. With a high-quality finish, the EK-STC Classic Fittings are an aesthetically appealing and secure option for your custom loop liquid cooling system. A non-intrusive, minimalistic look, with NO added branding at all.The locking ring is compressing the tubing wall underneath the ring, and this prevents the flexible tube from being pulled off the barb of the fitting. EK-STC Classic fittings are available in the three most popular color options such as nickel, black and black nickel. The barb and the ring are made of CNC machined brass and the seal is made quality rubber O-rings. The fitting barb surface is smooth and has no adequate gripping surface, but the inside of the bard is socketed with an 8mm hex Allen key pattern. It\'s highly recommended to use an Allen Key 8mm (purchased separately) to prevent skin damage to the fingertips while installing the fitting. Please, be advised not to use excessive force when attaching fitting barbs using Allen Key 8mm in order to prevent damage to other liquid cooling products!These fittings have guaranteed compatible with all other EK Water Blocks liquid cooling products.Technical data:- Thread: G1/4\" BSP; 4.5mm male thread length- Supported tube: 10 / 13mm ID / OD - (3/8\" / 1/2\" ID / OD)- Outer diameter of a fitting: 19mm- Installed height: 14.5mm- Compatible tubing: PVC, EPDM, Norprene, silicone, most types of flexible tube