Edison screw lamp bases: E12, E14, E26, E27, E39, E40 thread sizes — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/lamp-base-edison-screw/  (sheet CC BY 4.0)
Basis: Wikipedia Edison screw table (IEC 60061-1 / ANSI C81.67 values); numbers only
Catalog version: 2026-10-20

Sizes: see table below
- The number after E is the thread outer diameter in mm. E26 is the US medium base, E27 the European one; E12 is the US candelabra, E14 the European small base, E39 the US mogul.
- Pitch: E14 2.82 mm (9 threads per inch), E26 7 threads per inch (3.63 mm, computed 25.4 / 7), E27 3.62 mm, E40 6.35 mm. E12 and E39 pitch was not confirmed on a reachable page, so none is given.
- No file: the thread profile (flank angle, root and crest radius), base length and gauge shape are not published on any page available to Xem, and a plain cylinder at the major diameter would not be the base.

base  thread outer diameter, mm  pitch
E12 candelabra  12  not confirmed
E14 small  14  2.82 mm (9 per in)
E26 medium (US)  26  7 per in = 3.63 mm
E27 medium  27  3.62 mm
E39 mogul (US)  39  not confirmed
E40 goliath  40  6.35 mm

Files elsewhere (not hosted by Xem Studio; license as stated by the publisher):
- Wikipedia: Edison screw — web — CC BY-SA; facts only — https://en.wikipedia.org/wiki/Edison_screw

No true-size file yet: the published figures do not fix the whole shape; a measured scan is planned.
API: https://xemstudio.com/api/geometry?object=lamp-base-edison-screw