PrimoChill Rigid Compression Coupler to G 1/4 Female - Knurled Grip - Anodized Black - 2 Pack Connect Rigid tubes to any Male G 1/4 Fitting or Cap, Easily go from to Flex tubing to Rigid. Nickel Coated Brass interior, Interior Compression O-ring. Lightweight, low profile. Bright Aluminum Color, or Nickel Plated Black and Silver Patent Pending Design