Philidas^® Self-Locking Nuts

All-metal prevailing-torque lock nuts in A2 & A4 stainless — reusable, no insert, DIN & ISO certified. M4 to M24 held in stock.

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Certification & traceability Unique to PTS

Choose your certificate online and view batch numbers and country of origin for full traceability on every order.

Philidas® — Self-Locking NutsPhilidas A2Price per 100 · pack quantities shown

In stock Low On order

Size	Availability	Batch / Cert	Price / 100	Pack
M4DIN 982 Philidas A2	In stock 3,200	Cert & batch	£28.40	100
M5DIN 982 Philidas A2	In stock 2,800	Cert & batch	£32.60	100
M6DIN 982 Philidas A2	In stock 2,200	Cert & batch	£38.80	100
M8DIN 982 Philidas A2	In stock 1,600 +400 · 2–3 weeks	Cert & batch	£56.40	50
M10DIN 982 Philidas A2	In stock 1,100 +200 · 2–3 weeks	Cert & batch	£82.60	50
M12DIN 982 Philidas A2	In stock 750 +150 · 2–3 weeks	Cert & batch	£118.80	25
M16DIN 982 Philidas A2	Low stock 320 +100 · 2–3 weeks	Cert & batch	£188.50	25
M20DIN 982 Philidas A2	Low stock 110 +80 · 2–3 weeks	Cert & batch	£298.00	10
M24DIN 982 Philidas A2	Low stock 45 +40 · 2–3 weeks	Cert & batch	£448.00	10
M4DIN 982 Philidas A4	In stock 1,800	Cert & batch	£38.40	100
M5DIN 982 Philidas A4	In stock 1,500	Cert & batch	£44.60	100
M6DIN 982 Philidas A4	In stock 1,200	Cert & batch	£52.80	100
M8DIN 982 Philidas A4	In stock 850 +200 · 2–3 weeks	Cert & batch	£76.40	50
M10DIN 982 Philidas A4	In stock 580 +100 · 2–3 weeks	Cert & batch	£112.60	50
M12DIN 982 Philidas A4	Low stock 380 +80 · 2–3 weeks	Cert & batch	£158.80	25
M16DIN 982 Philidas A4	Low stock 140 +60 · 2–3 weeks	Cert & batch	£258.50	10
M20DIN 982 Philidas A4	No stock 0 +50 · 2–3 weeks	Cert & batch	£408.00	10
M6DIN 982 Philidas HT	Low stock 480	Cert & batch	£68.80	50
M8DIN 982 Philidas HT	Low stock 320	Cert & batch	£98.40	25
M10DIN 982 Philidas HT	Low stock 180 +100 · 2–3 weeks	Cert & batch	£148.60	25

Dimensional data

Size (d)	Pitch	A/F (s)	C/F (e)≈	Thick (m)
M1.0	0.25	2.50-2.40	2.89	0.80-0.55
M1.2	0.25	3.00-2.90	3.46	1.00-0.75
M1.4	0.30	3.00-2.90	3.46	1.20-0.95
M1.6	0.35	3.20-3.02	3.70	1.30-1.05
M1.7	0.35	3.50-3.38	4.04	1.40-1.15
M2	0.40	4.00-3.82	4.62	1.60-1.35
M2.3	0.40	4.50-4.32	5.20	1.80-1.55
M2.5	0.45	5.00-4.82	5.77	2.00-1.75
M2.6	0.45	5.00-4.82	5.77	2.00-1.75
M3	0.50	5.50-5.32	6.35	2.40-2.15
M3.5	0.60	6.00-5.82	6.93	2.80-2.55
M4	0.70	7.00-6.78	8.08	3.20-2.90
M5	0.80	8.00-7.78	9.24	4.00-3.70
M6	1.00	10.00-9.78	11.55	5.00-4.70
M7	1.00	11.00-10.73	12.70	5.50-5.20
M8	1.25	13.00-12.73	15.01	6.50-6.14
M10	1.50	17.00-16.73	19.63	8.00-7.64
M12	1.75	19.00-18.67	21.94	10.00-9.64
M14	2.00	22.00-21.67	25.40	11.00-10.30
M16	2.00	24.00-23.67	27.71	13.00-12.30
M18	2.50	27.00-26.16	31.18	15.00-14.30
M20	2.50	30.00-29.16	34.64	16.00-14.90
M22	2.50	32.00-31.00	36.95	18.00-16.90
M24	3.00	36.00-35.00	41.57	19.00-17.70
M27	3.00	41.00-40.00	47.34	22.00-20.70
M30	3.50	46.00-45.00	53.12	24.00-22.70
M33	3.50	50.00-49.00	57.74	26.00-24.70
M36	4.00	55.00-53.80	63.51	29.00-27.40
M39	4.00	60.00-58.80	69.28	31.00-29.40
M42	4.50	65.00-63.10	75.06	34.00-32.40
M45	4.50	70.00-68.10	80.83	36.00-34.40
M48	5.00	75.00-73.10	86.60	38.00-36.40
M52	5.00	80.00-78.10	92.38	42.00-40.40
M56	5.50	85.00-82.80	98.15	45.00-43.40

All dimensions in mm. ≈ across-corners (e) is calculated from nominal geometry as a guide. The drawing stays in view as you scroll the table.

Why Philidas® locking nuts?

The Philidas nut achieves locking through an elliptically distorted thread — no insert, no patch. Reusable up to 10 times without losing performance. All-metal, DIN & ISO, full traceability.

View all Philidas® products →

No insertall-metal

Up to 10×reuse cycles

60+ yrsexpertise

Batch & certificate

Choose your certificate, batch and country of originWhat are PMI & 3.1 certs?

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1 Choose certification

FastestNo certificateIncludedStandard documentation — dispatched fastest. PMI Certificate£83.27Positive material identification test. EN 10204 3.1£76.33Full mill cert — heat / batch traceable.

2 Choose a batch & country of origin

Batch	Country of origin	Certs available	Availability
82963	Italy	PMI · 3.1 · None	38,400 in stock	Select
TBC	—	PMI · None	57,800 · 2–3 weeks	Select

Selected: No certificatePMI Certificate · £83.27EN 10204 3.1 · £76.33CancelConfirm selection

Philidas®

About Philidas® locking nuts

The Philidas nut locks through an elliptically distorted thread — no nylon insert, no patch, nothing to degrade. It is all-metal, so it holds at temperature and can be reused up to ten times without losing prevailing torque.

Where they are used

Vibration-critical joints in rail, defence, motorsport and heavy plant, and anywhere a nylon insert would fail on heat.

More detail in the Knowledge Hub.

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