Xem Studiomeasured geometry

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

PCO 1881 neck finish, top to support-ring face (17.00)

PCO 1881 neck finish, top to support-ring face (17.00): bore Ø21.74, neck Ø24.94, thread Ø27.40, 2.7 mm pitch single-start right-hand, 650° of thread starting 1.7 below the top; tamper bead and support ring not drawn (see notes)

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

STEP STL free, CC BY 4.0 (credit "Xem Studio")

Let your AI pull this. Add https://xemstudio.com/mcp to Claude, ChatGPT, Cursor or any MCP client (free, no account, one minute) and it can look up exact sizes, mating fits and free STEP/STL from every chat.
Set it up →

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?

Other sizes