Over the moon with these pliers, had a screw which had been tight against a metal plate for over 30 years in a VCR. I couldn't loosen it off tried loads of bits and pliers. These pliers have a recess at the bottom of the jaws which helps grip the screw head. I wasn't confident they would work since the screw has a rounded head and when I tried my pliers they kept slipping off when I applied force, With these pliers they enclose the screw in the recess of the jaws and with a little effort the screw starts turning. Highly recommend these beauties!!