Proto® 1/2″ Drive Air Impact Wrench Review – Model J150WP

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Proto 1/2″ Drive Air Impact Wrench J150WP

Proto 1/2" Drive Air Impact Wrench

Manufacturer: Proto
Model number: J150WP
Price: $400
Power source: Pnuematic
Weight: 4.8 lbs

Impact wrenches are one of those essential shop tools that get used and abused daily and often get taken for granted. That’s why having a powerful, reliable, comfortable air impact driver is absolutely at the top of most mechanics must have lists. We recently had the pleasure of testing and reviewing a new air impact driver from Proto® Air Tools.

The Proto J150WP is a 1/2″ Drive Air Impact Wrench is a lightweight, powerful impact driver built for professional use. Some of the features include:

  • Stanley Proto J150WP Impact WrenchTitanium housing helps to reduce weight, improve balance and ensure maximum durability.
  • Ergonomically designed handle-forward design improves balance and control, helping to reduce operator fatigue.
  • Robust twin hammer mechanism for efficient energy transfer and long service life.
  • Ambidextrous forward/reverse lever can be actuated with a single hand, even with gloves on.
  • Three position power regulator for forward rotation. Reverse rotation operates at maximum for highest breakaway torque.
  • Feather throttle for maximum operator control.
  • Side-fed, 6-vane air motor for maximum power and efficiency.
  • Machined motor housing reduces number of parts, creating precision alignment, reducing wear, increasing efficiency and simplifying maintenance.
  • 360º Rotating Air Inlet Fitting.
  • Titanium Exhaust Deflector and Muffler.
  • Integrated Tethering Capability in all Proto® Air Tools.
  • Optional ProtoID™Air Fitting for RFID Tracking Capability. Visit for more information.Proto J150WP Impact Wrench

Powerful & Well Built

In order to really get an idea of how well the Proto J150WP performs we tested it at two locations. First off I tested it in my shop for a few days. Then we brought it to one of our local tire shops and let one of the tech’s use it to change wheels all day.

The first thing I noticed about this wrench is how powerful it is and how comfortable it is to use and hold. The weight and balance of this impact wrench make it easy to handle while imposing very little reactionary torque on the user. With very little effort we were consistently tightening lugs nuts to 80 ft-lbs of torque.

The titanium housing and rubber grip are very well built with an industrial looking design. The quality of the materials appear to be very good which should result in a long life in the hostile environment of busy shops.

Proto Air Impact Wrench at Tire Store

We also brought the J150WP down to the local tire store and let the guys in the shop use it for the day. The overall reaction was very positive. They too agreed that it’s powerful, comfortable and very durable looking. The guys were also very impressed with how easy it is to switch from forward to reverse. The three position regulator switch was also something they thought was a great feature. Overall the crew thought it was a very good air impact wrench.

Final Thoughts

The Proto 1/2″ Drive Air Impact Wrench (J150WP) is a high quality tool built for industrial/commercial applications. It’s powerful, comfortable and offers user friendly features. It’s certainly an impact wrench that I’m glad I now have in my shop and I’ll gladly recommend it to others looking for a new air impact wrench.

Proto 1/2" Drive Air Impact Wrench

About the author

Pat Askren

Contributing Columnist Pat Askren is a retired Fire Chief who spends his free time building custom cars, repairing appliances and an assortment of home improvement projects. He has extensive experience using an assortment of tools from each of those categories. Pat is a text book Do-It-Yourselfer who loves getting his hands dirty and finding the right tool for the job!Pat recently opened his own "hot rod" shop where he builds and restores custom cars with friends and family. His new shop is the perfect place to test tools especially ones focused on the auto industry.In his free time he enjoys fishing and spending time with his four grandchildren.

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