ZAW-421B3 3/8-Inch Air Wrench – Professional Two Hammer Pneumatic Impact Wrench with Side Exhaust
The ZAW-421B3 3/8-inch air wrench is designed for professionals who need power, precision, and durability in a compact tool. Featuring a two hammer impact mechanism, this pneumatic wrench delivers fast, consistent torque for a wide range of fastening tasks, making it ideal for automotive repair, assembly work, and machinery maintenance.
Reliable Mid-Size Performance
With its 3/8-inch drive size, the ZAW-421B3 is perfect for medium-duty applications, providing the torque needed for stubborn bolts without being bulky or heavy. The two hammer system ensures balanced power delivery, reduces vibration, and extends the tool’s service life.
Durable & Workshop-Ready
Built with a high-strength alloy housing and heat-treated internal components, this impact wrench is engineered to withstand frequent daily use in professional environments. The robust design ensures dependable performance under demanding conditions.
Efficient Side Exhaust Design
The side exhaust system directs airflow away from the work area, minimizing dust disturbance and keeping sensitive surfaces clean. This design also helps reduce noise and prevents air from blowing directly onto the operator’s hands or face.
Practical Work Examples:
Automotive Maintenance: Removing caliper bolts during brake service, loosening engine component fasteners, and assembling drivetrain parts.
Light Truck and Motorcycle Repair: Fastening suspension bolts, handlebar assemblies, and axle nuts.
Industrial Assembly: Installing mid-size bolts on machinery frames, conveyor lines, and equipment housings.
Appliance and Equipment Service: Tightening and removing bolts on generators, pumps, and air compressors.
Maintenance in Tight Spaces: Accessing bolts in engine bays, under dashboards, and inside machine enclosures.
Technical Specifications:
Drive Size: 3/8 inch
Impact Mechanism: Two Hammer
Exhaust Type: Side exhaust
Construction: High-strength alloy housing, heat-treated precision parts
Application Range: Medium-duty fastening for automotive, industrial, and equipment repair
Key Benefits:
Balanced power-to-weight ratio for comfortable, extended use
Two hammer mechanism for smoother, stronger impacts
Durable industrial-grade build for daily workshop use
Side exhaust for cleaner operation and reduced dust disturbance
Compact size for better access in confined spaces
Specification:
- Bolt Size Capacity: M10~M12
- Working Torque: 66(90)ft-lb(Nm)
- MAX. Torque: 177(240)ft-lb(Nm)
- Free Speed: 8000rpm
- Air Consumption: 283(10)l/min(cfm)
- Overall Length: 7.48(190)inch(mm)
- Air Inlet: 1/4P.T
- Net Weight: 2.34(1.06)lb(kg)
- Sound Level: 97db(A)
| Model | Bolt Size Capacity | Working Torque ft-lb(Nm) | MAX. Torque ft-lb(Nm) | Free Speed rpm | Air Consumption l/min(cfm) | Overall Length inch(mm) | Air Inlet P.T | Net Weight lbs(kgs) | Sound Level db(A) |
| ZAW-412B2 | M8 | 20(27) | 26(35) | 11000 | 127(4.5) | 7.01(178) | 1/4 | 1.5(0.68) | 89 |
| ZAW-412B3 | M8 | 20(27) | 26(35) | 11000 | 127(4.5) | 7.01(178) | 1/4 | 1.5(0.68) | 89 |
| ZAW-417B | M10 | 59(80) | 148(200) | 8000 | 212(7.5) | 8.86(225) | 1/4 | 2.36(1.07) | 90 |
| ZAW-910B1 | M10 | 59(80) | 96(130) | 8000 | 184(6.5) | 9.06(230) | 1/4 | 2.65(1.2) | 80 |
| ZAW-410B | M10 | 59(80) | 148(200) | 8300 | 212(7.5) | 7.48(190) | 1/4 | 2.16(0.98) | 94 |
| ZAW-421B3 | M10~M12 | 66(90) | 177(240) | 8000 | 283(10) | 7.48(190) | 1/4 | 2.34(1.06) | 97 |
| ZAW-211B | M12~M14 | 118(160) | 207(280) | 5500 | 240(8.5) | 10.24(260) | 1/4 | 3.75(1.7) | 85 |
| ZAW-241B | M16~M18 | 236(320) | 369(500) | 4400 | 283(10) | 13(330) | 1/4 | 7.5(3.4) | 95 |
Recommended Gauge Air Pressure: 60~90psi

