SAE J314 Wool Felt Grades — F-1 to F-55
The complete industrial wool-felt grade reference, cross-referenced to DIN 61200, ASTM D461, BSI and IS 282.
SAE J314 is the de-facto global classification for industrial wool felt. Each grade defines a target density and minimum wool content — and through those properties, a predictable set of mechanical, thermal and acoustic behaviours. Premier Felt manufactures across the full SAE range from our Bikaner facility. Use the table below to pick a grade, or send us a drawing and we'll spec it for you.
Quick guide — which SAE grade for which job?
Pressed wool, hardest
SAE F-1 → F-7
Oil seals, polishing wheels & bobs, machine bushings, valve packing, leather embossing, pump wicks.
Pressed wool, hard
SAE F-10 → F-13
Hydraulic washers, lubrication wicks, anti-vibration mounts, gaskets in high-pressure assemblies.
Wool/blend, medium-hard
SAE F-15 → F-26
General gasketing, dust seals, packing strips, weather stripping, sound dampers.
SAE soft / semi-hard
SAE F-50 → F-55
Cushioning, lining, sound absorption, padding, decorative articles, craft & insulation panels.
Complete SAE J314 grade chart
Densities are nominal, ± typical manufacturing tolerance. All grades available in thicknesses 1.5–75 mm and widths to 220 cm. Custom blends, colours and FR finishes available on request.
| SAE Grade | Hardness Class | Density (g/cm³) | Min. Wool Content | Colour | Typical Applications |
|---|---|---|---|---|---|
| F-1 | Extra Hard | 0.55–0.62 | 100% | White | Premium oil seals, valve packing, pressure pump wicks |
| F-2 | Extra Hard | 0.50–0.58 | 100% | White | Polishing wheels & bobs, jewellery polishing |
| F-3 | Extra Hard | 0.48–0.55 | 100% | White / Gray | Dental & ophthalmic polishing, fine metal finish |
| F-5 | Hard | 0.42–0.48 | 100% | White / Gray | Bushings, leather embossing, machine packing |
| F-7 | Hard | 0.38–0.44 | 100% | White / Gray | Marble polishing, glass polishing, hydraulic washers |
| F-10 | Hard | 0.34–0.40 | 90–100% | White / Gray | Oil-wick lubrication, anti-vibration pads |
| F-11 | Hard | 0.31–0.36 | 90–100% | White / Gray | General gasketing, sealing rings, dust seals |
| F-13 | Medium Hard | 0.28–0.32 | 80–100% | White / Gray | Sound damping, packing strips, vibration insulators |
| F-15 | Medium Hard | 0.26–0.30 | 80–100% | White / Gray | Industrial wipers, applicator pads, ink pads |
| F-20 | Medium Hard | 0.24–0.28 | 70–100% | White / Gray | Weatherstripping, dust skirts, general packing |
| F-26 | Medium Hard | 0.22–0.26 | 50–100% | White / Gray / Custom | Lining, cushioning, decorative articles |
| F-50 | Soft | 0.18–0.23 | 50–100% | Natural / Custom | Sound absorption panels, padding, packaging |
| F-51 | Soft | 0.16–0.21 | 50–100% | Natural / Custom | Saddle pads, equestrian boots, soft lining |
| F-55 | Soft | 0.15–0.19 | 50–100% | Natural / Custom | Furniture pads, craft articles, thermal insulation |
SAE ↔ DIN ↔ ASTM ↔ BSI ↔ IS cross-reference
If your drawing calls out a felt by anything other than an SAE grade, use the table below. Standards aren't perfectly identical, so for safety-critical applications we always test against the originating standard.
| SAE J314 | DIN 61200 | ASTM D461 Class | BSI BS 2471 | IS 282 | Hardness |
|---|---|---|---|---|---|
| F-1 / F-2 | F1 / F2 | Type A — Hard | Grade A | Class 1 | Extra Hard |
| F-3 / F-5 | F3 / F4 | Type A — Hard | Grade A | Class 1 | Extra Hard / Hard |
| F-7 / F-10 | F5 | Type B — Medium | Grade B | Class 2 | Hard |
| F-11 / F-13 | F6 | Type B — Medium | Grade B | Class 2 | Hard / Medium |
| F-15 / F-20 | F7 | Type C — Medium | Grade C | Class 3 | Medium Hard |
| F-26 | F8 | Type C | Grade C | Class 3 | Medium Hard |
| F-50 / F-51 | F10 | Type D — Soft | Grade D | Class 4 | Soft |
| F-55 | F11 | Type D — Soft | Grade D | Class 4 | Soft |
What density really tells you
SAE grade is shorthand for density and wool content — but the reason it matters is what those numbers predict:
- Higher density → higher tensile strength, lower air permeability, lower compressibility, higher abrasion resistance, finer polishing finish.
- Lower density → better sound absorption (NRC 0.64 at F-55 vs 0.45 at F-1), higher oil-wicking capillary height, higher compressibility, better cushioning.
- Higher wool % → better self-felting bond, longer service life, biodegradable end-of-life.
- Lower wool % (blended) → lower cost, can be tuned to higher temperatures with synthetic blends.
See our Technical Specifications page for the full comparative property table (air permeability, oil absorption, NRC, tensile/tear strength, coefficient of friction, max temperature).
Need help picking a grade?
Tell us the application, target dimensions and any constraints (temperature, fluid, fire rating). We'll recommend a grade, send a swatch, and quote within one business day.
Get a spec recommendation