Powerful and keeps what from

In my Opel Zafira A the rear wiper has been canceled. For days I had from time to time trying to get the rest of the wiper arm off. - With all possible and impossible methods, so that I almost gave up.

This two-arm puller is what I have not done for days, accomplished within a few minutes. - And now it is also clear why:

The two-arm puller acts at first sight ever quite robust. The arms are held by springs to the cone, with the distance of the gripping arms is adjusted. The correct setting for the rest of the wiper arm was found almost immediately.

When screwing down the thread fell to advance that the thread is quite flat, resulting in very little stroke per revolution leads, but probably accommodates the force action.

With bare hands, I could not muster enough force to dislodge the wiper arm. So I thought: All or Nothing. So slowly and carefully turned further with the pipe wrench the thread of the two-arm puller. A few turns later, a loud bang was heard, the wiper arm-rest was finally off and I was able to install the replacement part.

Conclusion: wiper arm-rest at last from everything else perfectly fine. The pretty thin lever on the upper part of the thread is barely moving his hand from a certain degree, but holding the cautious finishing tool with good (at least in my case).