4mm Outside Diameter Brass tube available with 0.225mm or 0.45mm wall.
The 4mm 0.225mm has an inside diameter of 3.5mm manufactured by K and S Metals
The 4mm 0.45mm has an inside diameter of 3mm manufactured by Albion Alloys.
The 0.225mm wall tube is part of the telescopic brass tube range where the following applies
2mm 0.225mm wall slides into 2.5mm 0.225mm wall
2.5mm 0.225mm wall slides into 3mm 0.225mm wall
3mm 0.225mm wall slides into 3.5mm 0.225mm wall
3.5mm 0.225mm wall slides into 4mm 0.225mm wall
4mm 0.225mm wall slides into 4.5mm 0.225mm wall
4.5mm 0.225mm wall slides into 5mm 0.225mm wall
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