Unthreaded round spacers by ID and OD: M2–M5 brass and aluminium sleeve spacers (Essentra, JC Fasteners, Keystone) + 10 tube models — dimension sheet Source: Xem Studio, https://xemstudio.com/objects/round-spacers-unthreaded-id-od/ (sheet CC BY 4.0) Basis: Essentra's brass round unthreaded spacer listing (three pages read), JC Fasteners' aluminium E5C18 data sheet (M2 to M5), Keystone Electronics' round clear-hole spacer datasheets; ten tube envelopes as files Catalog version: 2026-10-20 Overall (mm): length 10.0, width 10.0, height 10.0 - Millimetres unless marked. Round unthreaded spacers (sleeve spacers) by inside diameter, outside diameter and length. Essentra's brass spacers: ID / OD pairs 2.2 / 4.0, 2.5 / 5.0, 3.2 / 6.0, 4.3 / 8.0, 5.3 / 10.0; the lengths shown are those seen on three of the five listing pages (54 results in all), so they are examples, not the full range. JC Fasteners' E5C18 aluminium spacers: M2 2.2 / 5.0, M2.5 2.7 / 5.0, M3 3.2 / 5.0, M4 4.3 / 6.0, M5 5.3 / 7.0, with lengths 3 (or 4, 5) to 50 mm as listed; the sheet states no tolerances and says its data is informative. - The IDs are clearance sizes for the screw (2.2 for M2, 3.2 for M3, 4.3 for M4, 5.3 for M5, as the makers list them); the two makers differ in OD for the same bore (3.2 ID: OD 6.0 Essentra, OD 5.0 JC) and in the M2.5 ID (2.5 Essentra, 2.7 JC), so choose by the OD you need. Keystone's round clear-hole spacers (inch) have OD 0.250 or 0.312 in and lengths 0.125 to 2 in for #4, #6, #8 and #10 screws in aluminium, brass, nylon 6/6 or phenolic; part 3458 is 0.250 in OD × 0.375 in long (Newark lists a 3.048 mm bore for it; the Keystone page does not give the ID). - Files: ten plain tubes at the published ID and OD, drawn at an example length of 10 mm (Xem's choice; every size is available in more than one length). Chamfers, if any, are not published. Threaded standoffs: threaded-standoffs-metric and threaded-standoffs-hex-m4-m6-and-inch. Shaft spacers (Ø3 / Ø5 / Ø8): shaft-collars-clips-and-shafts. Essentra offers CAD per part on its site; McMaster-Carr sells unthreaded spacers (made to order and stock); both linked, not copied. maker / material ID (mm) OD (mm) lengths (mm) screw Essentra, brass 2.2 4.0 10 (seen on three of the listing pages) M2 – M5 screw clearance by ID Essentra, brass 2.5 5.0 1, 2, 3, 5, 6, 7, 8, 20 (seen on three of the listing pages) M2 – M5 screw clearance by ID Essentra, brass 3.2 6.0 1, 3, 4, 5, 6, 7, 8, 9, 10, 12, 15, 25, 30 (seen on three of the listing pages) M2 – M5 screw clearance by ID Essentra, brass 4.3 8.0 3, 5, 7, 8, 10, 12, 15, 25, 30, 35, 40 (seen on three of the listing pages) M2 – M5 screw clearance by ID Essentra, brass 5.3 10.0 2, 3, 4, 5, 6, 7, 8, 10, 15, 18, 30 (seen on three of the listing pages) M2 – M5 screw clearance by ID JC Fasteners E5C18, aluminium 6061 (M2) 2.2 5.0 3, 4, 5, 6, 8, 10, 12, 15, 20, 25 M2 screw JC Fasteners E5C18, aluminium 6061 (M2.5) 2.7 5.0 3, 4, 5, 6, 8, 10, 12, 15, 20, 25, 30, 35, 40 M2.5 screw JC Fasteners E5C18, aluminium 6061 (M3) 3.2 5.0 3, 4, 5, 6, 8, 10, 12, 15, 20, 25, 30, 35, 40, 45, 50 M3 screw JC Fasteners E5C18, aluminium 6061 (M4) 4.3 6.0 4, 5, 6, 8, 10, 12, 15, 20, 25, 30, 35, 40, 45, 50 M4 screw JC Fasteners E5C18, aluminium 6061 (M5) 5.3 7.0 5, 6, 8, 10, 12, 15, 20, 25, 30, 35, 40, 45, 50 M5 screw Keystone 3458, aluminium, clear Iridite 3.048 mm bore (Newark; not on the Keystone page) 0.250 in (6.35 mm) 0.375 in (9.525 mm) #4 / M3 Keystone 4264, aluminium not listed on the pages read not listed on the pages read 0.625 in (15.88 mm) #10 Keystone round clear-hole spacer family — 0.250 or 0.312 in 0.125 to 2 in #4, #6, #8, #10 clearance; aluminium, brass, nylon 6/6, phenolic; threaded or unthreaded Files elsewhere (not hosted by Xem Studio; license as stated by the publisher): - Essentra Components: Round unthreaded metal spacers (brass): inside diameter, outside diameter, length per part (54 results; three listing pages read) — web, CAD per part — Maker / distributor page; dimensions are facts [verify license at link] — https://www.essentracomponents.com/en-sg/p/round-unthreaded-metal-spacers - JC Fasteners (data sheet): Round spacer E5C18, aluminium 6061: M2 to M5 inner / outer diameter and lengths 3 to 50 mm — web — Maker data sheet; numbers only — https://www.jcfasteners.com/wp-content/uploads/Round-Spacer-E5C18-AL-6061.pdf - Keystone Electronics (datasheet via GlobalSpec) and Mouser: Round clear-hole spacers: OD 0.250 / 0.312 in, length 0.125 to 2 in, #4 / #6 / #8 / #10 clearance; part 3458 (aluminium, 0.250 OD, 0.375 long, #4 / M3) and 4264 (#10, 0.625 long) — web — Maker datasheet; numbers only — https://datasheets.globalspec.com/ds/keystone-electronics/3458/a34a0128-a131-4612-b7cc-9d1d32503ab1 - McMaster-Carr: Unthreaded spacers (made to order and stock) (free STEP/IGES per part, for your own design use; no redistribution) — STEP, IGES, PDF — McMaster-Carr site terms: personal design use, no redistribution [verify license at link] — https://www.mcmaster.com/products/shims/made-to-order-unthreaded-spacers Free files (CC BY 4.0, Xem Studio; STEP + STL, 10 parts): https://xemstudio.com/files/hardware/round-spacers-unthreaded-id-od/index.json API: https://xemstudio.com/api/geometry?object=round-spacers-unthreaded-id-od