Library › Hardware › Knobs, handles & feet ·

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? · Standard part · basis: JW Winco's GN 300 table (inch and metric), cross-checked against EWM, Galaxus and Monroe listings

Also called: gn 300, gn 300 clamping lever, adjustable clamping lever m8, adjustable hand lever m10, ratchet clamping lever m6, clamping lever 63 mm m8, tension lever m12 108, gn 300 l1 63 l2 50, adjustable lever 1/4-20, adjustable lever 3/8-16, clamping lever thread size, clamping lever stud length, ratcheting handle zinc die-cast, indexing handle m8

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. Mating features

sizes: 33 in table

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.

Adjustable clamping levers GN 300 (ratchet / tension levers): lever… size chart

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

Mating features

Drawn at the exact size. Open press, slide, run and socket features by your process's clearance (tolerances by process); leave designed gaps and clamp fits 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

Where the files are

Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.

JW Winco	GN 300 adjustable levers, zinc die-cast, threaded stud, inch and metric: l1, thread, stud length l2, d3, d4, h1 to h4	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)	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	web	Publisher's page; dimensions are facts

Xem scan

File coming

No downloadable true-size file yet: the published figures do not fix the whole shape, and Xem never guesses a number. A measured scan is planned; request it and it moves up.

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 →

Plain text: sheet.txt · JSON: /api/geometry?object=adjustable-clamping-levers-gn-300

Schematic, not to scale.