They don&#x27;t last in a pro shop. We have about five sets right now at my shop and have gone through more. Of those sets more than half of the phillips head bits are chipped and broken. Anything marked J0* or PH0* is particularly fragile.  
The material doesn&#x27;t feel anything like the tool steel that my auto repair tools are made of. The iFixit bits feel light and flimsy.