Package Includes: 2 pcs G1/4" Male to Male Mini Extender Fittings. Thread size: G1/4" Male to Male, connection diameter: 6 mm. With silver chrome plated on the surface. Material: Male to Male Fitting is made of high quality copper and stainless steel, sturdy, corrosion resistant and durable. Design: Concealed O-ring design for leak-proof and sealing, mainly used for quick couplings of air pipes and pneumatic tools, you can connect and disconnect pipes without tools. Application: suitable for PC water cooling system fittings.