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Makita GA4542C SJS II High‑Power Angle Grinder

The Makita 4-1/2” SJS™II High Power Angle Grinder (GA4542C) combines power, convenience, comfort and motor-protection features for longer-lasting industrial performance. It is ideal for cutting, grinding ferrous metal, paint and rust removal, shipyard maintenance, metal polishing, general steel grinding, auto repair work, cutting brick and masonry, restoration work, and more.

The GA4542C is equipped with SJS™II, a mechanical gear drive system to help prevent motor and gear damage by dampening the force on the gear when the wheel is forced to stop. SJS™II is also features a leaf spring and cam gear drive mechanism that is engineered to reduce vibration for increased operator comfort during extended use.

The 12 AMP motor delivers 2,800-11,000 RPM for versatility and maximum productivity. Labyrinth construction protects the motor with a complex set of channels, prohibiting dust and contamination from entering the motor. Additional protection features include a zig-zag epoxy applied to both sides of the armature coil, and a powder-coating to the field. This forms a barrier under rotation and is engineered to protect from dust and debris penetration for longer tool life.


Powerful 12.0 AMP motor delivers more output and variable (2,800 – 11,000) RPM

SJS™II provides a leaf spring and cam gear drive mechanism that is engineered to reduce vibration for increased operator comfort during extended use

Vibration absorbing side handle provides increased comfort on the job

Electronic controller provides constant speed control which automatically applies additional power to the motor to maintain speed under load

Electronic controller provides soft start which suppresses start-up reaction for smooth start-ups and longer gear life

Electronic controller provides an electronic current limiter which helps protect the motor from overload in high torque applications

Variable speed control dial enables user to match the speed to the application

Labyrinth construction seals and protects the drive gear and bearings from dust and debris for increased durability

Motor fan is designed with enlarged fins for increased air flow and a cooler running motor

Complete zig-zag epoxy is applied to both sides of the armature coil and a powder coating to the field for protection from debris and longer tool life

Spiral bevel gears for smoother rotations and a more efficient transfer of energy

Fully aluminum constructed gear housing provides superior gear alignment and smooth transmission for increased durability and comfort

“Tool-less” wheel guard for easy adjustment

Slide switch with lock-on for continuous use

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