Stanley Proto's Obstacle Insert Sets feature a reverse-ratcheting S-shaped design
Blackhawk by Proto, a sub-brand of Stanley Proto industrial tools, introduces Obstacle Insert Sets. Each set includes one 8-inch wrench body, six flank adaptors and an equal number of box heads. Each flank adaptor is designed to slip into one of the wrench openings, while each box head attaches to its corresponding flank adaptor. Sets are available in Fractional (3/8 in. to 7/8 in.) and Metric (10 mm to 22 mm) versions.
The wrench body has been engineered so that the interchangeable heads do not reduce torque capacity: once in place, the adaptor transfers torque forces to the wrench body, minimizing stress on the adaptor. While the adaptors are held in place with a locking ring, they can be disengaged via a thumb release. Obstacle Insert Sets' S-shaped design is engineered to allow a greater arc swing.