# Adjustable clamping levers GN 300 (ratchet / tension levers): lever length 30 to 108 mm, thread M3 to M16 and inch, stud length, hub dimensions

> What are the dimensions of a GN 300 adjustable clamping lever: lever length, thread, stud length and the hub and boss dimensions?

- Category: Hardware › Knobs, handles & feet
- Kind: Standard part
- Basis: JW Winco's GN 300 table (inch and metric), cross-checked against EWM, Galaxus and Monroe listings
- Page: https://xemstudio.com/objects/adjustable-clamping-levers-gn-300/ · JSON: https://xemstudio.com/api/geometry?object=adjustable-clamping-levers-gn-300 · Plain text: https://xemstudio.com/objects/adjustable-clamping-levers-gn-300/sheet.txt
- License: dimension sheet CC BY 4.0 (Xem Studio); files CC BY 4.0 or their publisher's license
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**Exact dimensions.** Every file is drawn at true size with no tolerance added. The holes and pins that meet another part are listed below under Mating features, with the fit each joint needs; open those by your process's clearance before making the part.

## Notes

- GN 300 adjustable clamping levers (ratchet levers, 'indexing' hand levers, tension levers): a zinc die-cast lever on a steel serrated insert with a threaded stud. Pull the lever up, swivel it to a clear position and release; the serrations re-engage. The table is JW Winco's GN 300 (threaded stud, steel components, black oxide), inch and metric threads, six lever sizes. Each row is one lever size and thread; stud lengths l2 are the stock lengths in mm (the part number carries them: 3T45A19K is 1/4-20 × 45 mm). Special threads and lengths on request.
- d3, d4, h1 to h4 are printed by JW Winco without definitions; they are the same for every thread of a lever size. The only difference between the inch-thread and metric-thread tables is d4 for the 30 mm lever: 12.5 on the inch-thread rows and 12 on the metric-thread rows (both as printed; .49 in = 12.5 mm). Cross-check: the GN 300 listings at EWM (M12 l1 108 × l2 63; M12 l1 92 × l2 40; M10 l1 78 × l2 32), Galaxus (M8 63 × 50; M16 108 × 32 under GN 300.1) match rows of this table.
- Related versions (not tabled): GN 300.1 (stainless components), GN 300.4 (increased clamping force; Monroe's sheet lists four sizes l1 63 / 78 / 92 / 108 for M6 / M8 / M10 / M12 with its own letter set R, D, H, H1, h1, h2, d2, h that is not comparable), GN 300.5 (all stainless, l1 45 and 63 in the JW Winco sheet), GN 302 (straight lever) and GN 303.2 (push button, own page).
- Numbers only: the lever's curved outline is not published as coordinates, so no file is made. Mounting: a tapped hole of the stud thread, or a through hole and the lever's own insert.

## Mating features (exact size; open press / slide / run / socket by your process clearance, leave designed and clamp as drawn)

| feature | exact | mates with | fit | files |
|---|---|---|---|---|
| stud thread d1 × l2 | M3 to M16 and #10-32 to 5/8-11, stud 10 to 120 mm | a tapped hole of the same thread (or through hole and nut); the stud is a plain cylinder at the nominal major diameter | designed | all |

## Sizes

| lever length l1, mm | thread d1 | stud lengths l2, mm | d3, mm | d4, mm | h1, mm | h2, mm | h3, mm | h4, mm |
|---|---|---|---|---|---|---|---|---|
| 30 | 10-32 | 10, 12, 16, 20, 25, 32 | 10 | 12.5 | 26.5 | 4 | 35 | 3.5 |
| 30 | 10-24 | 12, 16, 20, 25, 32 | 10 | 12.5 | 26.5 | 4 | 35 | 3.5 |
| 30 | 1/4-20 | 10, 12, 16, 20, 25, 32, 40, 45 | 10 | 12.5 | 26.5 | 4 | 35 | 3.5 |
| 30 | M3 | 10, 12, 16, 20, 25, 32 | 10 | 12 | 26.5 | 4 | 35 | 3.5 |
| 30 | M4 | 10, 12, 16, 20, 25, 32 | 10 | 12 | 26.5 | 4 | 35 | 3.5 |
| 30 | M5 | 12, 16, 20, 25, 32, 40, 50 | 10 | 12 | 26.5 | 4 | 35 | 3.5 |
| 30 | M6 | 10, 12, 16, 20, 25, 32, 40, 45, 50 | 10 | 12 | 26.5 | 4 | 35 | 3.5 |
| 45 | 10-32 | 10, 12, 16, 20, 25, 32 | 10 | 13 | 24.5 | 4 | 35 | 3.5 |
| 45 | 10-24 | 12, 16, 20, 25, 32 | 10 | 13 | 24.5 | 4 | 35 | 3.5 |
| 45 | 1/4-20 | 10, 12, 16, 20, 25, 32, 40, 45 | 10 | 13 | 24.5 | 4 | 35 | 3.5 |
| 45 | M4 | 10, 12, 16, 20, 25, 32 | 10 | 13 | 24.5 | 4 | 35 | 3.5 |
| 45 | M5 | 12, 16, 20, 25, 32, 40, 50 | 10 | 13 | 24.5 | 4 | 35 | 3.5 |
| 45 | M6 | 10, 12, 16, 20, 25, 32, 40, 45, 50 | 10 | 13 | 24.5 | 4 | 35 | 3.5 |
| 63 | 1/4-20 | 12, 16, 20, 25 | 13.5 | 17.5 | 31 | 6.5 | 45 | 4 |
| 63 | 5/16-18 | 12, 16, 20, 25, 32, 40, 45, 50, 63 | 13.5 | 17.5 | 31 | 6.5 | 45 | 4 |
| 63 | 3/8-16 | 16, 20, 25, 32, 40, 45, 50, 63 | 13.5 | 17.5 | 31 | 6.5 | 45 | 4 |
| 63 | M6 | 12, 16, 20, 25, 32, 40, 50, 63 | 13.5 | 17.5 | 31 | 6.5 | 45 | 4 |
| 63 | M8 | 12, 16, 20, 25, 32, 40, 45, 50, 63 | 13.5 | 17.5 | 31 | 6.5 | 45 | 4 |
| 63 | M10 | 16, 20, 25, 32, 40, 45, 50, 63, 80 | 13.5 | 17.5 | 31 | 6.5 | 45 | 4 |
| 78 | 3/8-16 | 16, 20, 25, 32, 40, 45, 50, 63 | 16 | 21 | 36 | 8 | 55 | 4 |
| 78 | 1/2-13 | 16, 20, 25, 32, 40, 45, 50 | 16 | 21 | 36 | 8 | 55 | 4 |
| 78 | M8 | 16, 20, 25, 32, 40, 45, 50, 63, 80 | 16 | 21 | 36 | 8 | 55 | 4 |
| 78 | M10 | 16, 20, 25, 32, 40, 45, 50, 63, 80 | 16 | 21 | 36 | 8 | 55 | 4 |
| 78 | M12 | 25, 32, 40, 50, 63, 80 | 16 | 21 | 36 | 8 | 55 | 4 |
| 92 | 3/8-16 | 16, 20, 25, 32, 40, 45, 50, 63 | 19 | 24 | 43 | 11 | 65 | 4 |
| 92 | 1/2-13 | 16, 20, 25, 32, 35, 40, 45, 50, 63 | 19 | 24 | 43 | 11 | 65 | 4 |
| 92 | M10 | 16, 20, 25, 32, 40, 45, 50, 63, 80 | 19 | 24 | 43 | 11 | 65 | 4 |
| 92 | M12 | 16, 20, 25, 32, 35, 40, 45, 50, 63, 80 | 19 | 24 | 43 | 11 | 65 | 4 |
| 92 | M16 | 25, 32, 40, 50, 63, 80 | 19 | 24 | 43 | 11 | 65 | 4 |
| 108 | 1/2-13 | 25, 32, 40, 50, 55, 63 | 23 | 30 | 50.5 | 12 | 76 | 5 |
| 108 | 5/8-11 | 32, 40, 50, 55, 63 | 23 | 30 | 50.5 | 12 | 76 | 5 |
| 108 | M12 | 25, 32, 40, 50, 63, 80, 120 | 23 | 30 | 50.5 | 12 | 76 | 5 |
| 108 | M16 | 25, 32, 40, 50, 63, 80, 120 | 23 | 30 | 50.5 | 12 | 76 | 5 |

## Where the files are

- JW Winco: [GN 300 adjustable levers, zinc die-cast, threaded stud, inch and metric: l1, thread, stud length l2, d3, d4, h1 to h4](https://doc.pegamo.es/www/componente/doc/A651547F08F44403B906A7F5D088E2F4.pdf) — web — Publisher's page; dimensions are facts
- EWM sales (Ganter GN 300 listings): [GN 300 d1 M12 l1 108 l2 63; M12 l1 92 l2 40; M10 l1 78 l2 32 (cross-check)](https://ewm-sales.com/en/Industrial_and_craft_supplies/Technical_trade/General_industrial_supplies/Machine_operating_element_and_standard_element_accessories/Clamping_levers/Verstellbarer_Klemmhebel_GN_300_d1_M_12mm_l1_108mm_l2_63mm_AG_GANTER--4601000488.html) — web — Publisher's page; dimensions are facts
- Monroe Engineering: [GN 300.4 adjustable levers with increased clamping force: sizes 63 / 78 / 92 / 108, M6 to M12](https://catalog.monroeengineering.com/Asset/GN-300-4-Adjustable-Handles-with-High-Tightening-Clamping-Force.pdf) — web — Publisher's page; dimensions are facts

## Questions

**What lever length goes with an M8 GN 300?**

63 mm (or 78 mm); the 63 mm lever takes M6, M8 and M10 and the 78 mm lever M8, M10 and M12.

**What stud lengths does a GN 300 have?**

From 10 mm (small levers) to 120 mm (108 mm lever): for M8 on the 63 mm lever 12, 16, 20, 25, 32, 40, 45, 50 and 63 mm.

**What is the hub size of a GN 300 63 mm lever?**

d3 13.5, d4 17.5, h1 31, h2 6.5, h3 45, h4 4 mm (letters as printed by JW Winco).

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