1/2" US (0.700" OD) vs 13 mm (about 1/2" nominal): specs compared

Updated 05 September 2026.

6
specs differ

1/2" US (0.700" OD) and 13 mm (about 1/2" nominal) differ on 6 specs: outer diameter, inner diameter, fitting type, trap, role, common kit.

Spec1/2" US (0.700" OD)13 mm (about 1/2" nominal)
Outer diameter0.700 inch (varies 0.620 to 0.710 inch by brand)about 13 mm (barb sized 13 mm / 0.51 inch)
Inner diameterabout 0.600 inch
Fitting type.700 barb, compression or Perma-Locinsert barb or compression collar
Traplabelled 1/2 inch but not 16 mm metric
Rolesmall supply / branch line off a 16 mm main
Common kitsold paired with 16 mm pipe in starter sets

Questions and answers

How do 1/2" US (0.700" OD) and 13 mm (about 1/2" nominal) compare?

1/2" US (0.700" OD) and 13 mm (about 1/2" nominal) differ on 6 specs: outer diameter, inner diameter, fitting type, trap, role, common kit.

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