Aquarium CO2 Tank Cylinder Adapter Converter Bolt Nut for Co2 Regulator, W21.8

Material: 304 dtainless steel; 4 size available: W21.8 to G5/8; G5/8 to W21.8; M22x1.5 to G5/8; G5/8 to M22x1.5. W21.8 to G5/8: Inner Thread: W21.8, Outer Thread: G5/8. G5/8 to W21.8: Inner Thread: G5/8, Outer Thread: W21.8.

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