Imperial UNC brass hex standoff — engineering drawing (Brassland).
Specification
| Standard | Industry catalog convention — there is no ASME dimensional standard for hex standoffs |
| Type | Hex standoffs and spacers: male-female, female-female, male-male |
| Thread | 2-56 to 1/4-20 UNC (UNF such as 10-32 included); to ASME B1.1, class 2A / 2B |
| Material | C36000 free-machining brass (UNS) — EN twin CW614N (CuZn39Pb3); lead-free C69300 / CW724R on request |
| Certificate | EN 10204 3.1 per shipment; 3.2 on request |
Thread ↔ hex across-flats pairings (US catalog standard)
| Thread | Standard hex A/F | Also offered |
|---|---|---|
| 2-56 | 3/16 in. | 1/8 in. (some catalog lines) |
| 4-40 | 3/16 in. and 1/4 in. | — |
| 6-32 | 1/4 in. (most common) | 5/16 in. · 3/8 in. |
| 8-32 | 1/4 in. and 5/16 in. | 3/8 in. · 1/2 in. |
| 10-32 | 5/16 in. and 3/8 in. | 1/4 in. (thin-wall) · 1/2 in. |
| 1/4-20 | 1/2 in. | 5/8 in. (some catalog lines) |
Pairings follow the de-facto catalog convention shared across major US standoff manufacturers (verified against multiple published catalogs, July 2026) — not an ASME table. Brassland machines any thread–hex combination to your drawing, including 1/4-20 on 3/8 in. hex per our standoff range. Full dimension chart: imperial standoff dimension chart →
Lengths & thread depths (catalog conventions)
Standard stocked body lengths across US catalogs run 1/8 in. through 2 in. in 1/16 in. steps; specific catalog lines extend to 10 in. for the larger hex bodies, and custom lengths are commonly offered in 1/32 in. increments. A typical published catalog length tolerance is ±.005 in. up to 4 in., ±.008 in. from 4–6 in. and ±.010 in. over 6 in. Female-female standoffs are tapped through on short bodies; long bodies are tapped from both ends, with internal thread depth adjusted where the body will not permit full depth — exact tap depth is manufacturer-specific, so call it out on your drawing. Male-female stud length likewise follows the individual catalog drawing. Brassland machines all of these features to your print rather than to any one catalog.
Applications
Imperial hex standoffs carry PCB-to-chassis and board-to-board stacks in electronics built to US drawings — instrumentation, control panels, telecom and power hardware. Brass standoffs are conductive (grounding paths), non-magnetic and corrosion resistant; tin or nickel plating is available where solderability or a harder surface is needed. The metric range is on our brass hex standoffs page.
Imperial & UNC range
Related pages
Metric M2.5–M8 range — M-F / F-F / M-M.
View →ProductThreaded terminal blocks for boards.
View →IndustryBoard hardware and spacers.
View →MaterialUS free-machining brass datasheet.
View →Product#0–3/8 nuts that pair with standoffs.
View →ToolUNC tap drills at a glance.
View →Quote in 24 hours.
Give the standard, thread, finish and quantity. We machine inch-series brass parts in Jamnagar, India, and export to 40+ countries.
Sources & references
Hex/thread pairings, length ranges and thread-depth conventions verified across multiple published US standoff manufacturer catalogs and cross-reference tables (July 2026). Because no ASME dimensional standard exists for hex standoffs, dimensions on this page are labeled as catalog conventions; the controlling document for any order is your drawing. Threads per ASME B1.1.
Frequently asked questions
No. Electronic hex standoffs have no ASME dimensional standard — hex across-flats, lengths and thread depths are industry catalog conventions that the major US manufacturers share. That is why standoff pages quote catalog pairings and why the controlling document for an order is always the drawing.
3/16 in. or 1/4 in. across flats — both are stocked as standard across US catalogs. 6-32 most commonly runs on 1/4 in. hex, 8-32 on 1/4 or 5/16 in., and 10-32 on 5/16 or 3/8 in.
1/2 in. across flats is the verified common catalog size, with 5/8 in. offered in some lines. Brassland also machines 1/4-20 on 3/8 in. hex to order as part of our standoff range.
Short bodies are tapped through. On long bodies the threads are tapped from both ends, and internal thread depth is adjusted where the body cannot take full depth — the exact minimum tap depth is manufacturer-specific, so specify it on your drawing.
C36000 free-machining brass (EN twin CW614N / CuZn39Pb3), plain or tin / nickel plated. Lead-free silicon brass is available for RoHS-sensitive assemblies. Made to order with EN 10204 3.1 certificates per shipment.