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Library › Hardware › PET bottle necks: PCO 1881 (soda, 28 mm) and 38 mm

38-400 (SPI/GPI) neck finish, 10.24 tall

38-400 (SPI/GPI) neck finish, 10.24 tall: thread T Ø37.19, E Ø34.80, bore Ø25.07, 6 TPI (4.233 mm pitch) single-start right-hand, one turn (360°) starting 1.17 below the top, L-form 2.39 wide

Exact dimensions. True size, no printing tolerance added. Threads are plain cylinders at the major diameter.

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From the full sheet

PET bottle necks: PCO 1881 (soda, 28 mm) and 38 mm (milk/juice): every size, notes, mating features and sources. What is the thread size of a soda bottle cap?

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