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Torque Adapter 0.5 Nm for 1/4 Inch Bits, Narrow Version - Bernstein 4-991-05
The torque adapter 4-991-05 delivers a factory-preset tightening torque of 0.5 Nm with a tolerance of only +/-10% for at least 20,000 clicks. It is clamped between a holding tool and a 1/4 inch bit and suits delicate screw connections on electronic devices and in precision mechanics.
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- Technical questions clarified with the manufacturer
Description
Tightening delicate screws on electronic devices calls for more than a standard bit holder when an exact torque is required. The adapter 4-991-05 fits between a holding tool and a 1/4 inch bit and applies a factory-preset tightening torque of 0.5 Nm.
Benefits
- Precise tightening torque of 0.5 Nm with a tolerance of only +/-10% for at least 20,000 clicks.
- Clear click sound at the set torque, overtightening the screw is ruled out.
- No torque unlocking when loosening, giving 30% higher loosening torque without extra tools.
- Fits any standard 1/4 inch holding tool to DIN 3126 and holds bits with a magnetic seat.
- Compact design at Ø 10 mm with an overall length of only 34.5 mm and 15 g weight.
Application
- Exact tightening of small screws on electronic devices and in quick-change systems.
- Use in robotic stations, aerospace, and medical technology, wherever accurate torque is needed.
- Manual operation at any workbench, or with power tools at max. 100 rpm and minimal click repetition.
Standards and Delivery Data
- Tested according to DIN EN ISO 6789 for manually operated torque screwdriving tools.
- EAN 4250838533973
- Customs tariff number 82041100
- Country of origin Taiwan
Technical data
| Feature | Value |
|---|---|
| Preset | precise for at least 20,000 clicks |
| Tolerance | +/-10% (factory certificate on request) |
| Tightening torque | 0.5 Nm / 5.1 Kgfcm / 4.4 in-lb |
| Bit holder | magnetic, 1/4 inch hexagon 6.35 mm (DIN 3126) |
| Drive | 1/4 inch hex shank 6.35 mm (DIN 3126) |
| Material | alloyed steel |
| Adapter diameter | 10 mm (narrow version) |
| Adapter length | 24.5 mm (without shank) |
| Overall length | 34.5 mm |
| Weight | 15 g |
| Manufacturer | Bernstein |
| Manufacturer Nr. | 4-991-05 |
| EAN | 4250838533973 |
| HS-Code | 82041100 |
| GPSR manufacturer information | BERNSTEIN Werkzeugfabrik Industriehof Trecknase 1 DE-42897 Remscheid www.bernstein-werkzeuge.de |
| Condition of article | New |
| Article authenticity | Original product |
| Norm | DIN 3126, DIN EN ISO 6789 |
Downloads
Datasheet
Certificate
Other
- Cases and Sets EN
- Bernstein Catalogue Pages Ball Joint Vices and Holders EN
- Bernstein Catalogue Pages VDE Tools EN
- Bernstein Catalogue Pages Pliers EN
- Bernstein Catalogue Pages Screwing Tools, Torque and Bits EN
- Bernstein ESD Guide EN
- Drehmoment Schraubendreher DE
- Kugelgelenk Schraubstock DE
- Schonbacken DE
- Bernstein Katalogseiten Schraubstöcke und Halter DE
- ESD Leifaden DE
- Bernstein Katalogseiten ESD Arbeitsplatz und ESD Handwerkzeuge DE
- Bernstein Katalogseiten Pinzetten DE
- Bernstein Katalogseiten VDE Werkzeuge DE
- Zangen DE
Accessories
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Item BS-4-970-GTorque Adapter 0.3 Nm Narrow Version for 1/4 Inch Bits - Bernstein 4-991-03
Item BS-4-991-03Torque Adapter 0.4 Nm Narrow Version for 1/4 Inch Bits - Bernstein 4-991-04
Item BS-4-991-04Torque Adapter 0.2 Nm Narrow Version for 1/4 Inch Bits - Bernstein 4-991-02
Item BS-4-991-02Torque Adapter 0.7 Nm for C4 Bits, 4 mm Hex, ±10% Tolerance - Bernstein 4-977
Item BS-4-977Torque Adapter 5.5 Nm for 1/4 Inch Bits to DIN EN ISO 6789 - Bernstein 4-988-5
Item BS-4-988-5Torque Adapter 3.5 Nm for 1/4 Inch Bits with Magnetic Bit Holder 6.35 mm - Bernstein 4-986-5
Item BS-4-986-5Questions about this item
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