Have 4 them in use since 1999, a broke and had bought a replacement, which was only a short time in the spare, just I could give it back in the warranty period. The company had since no device to exchange and I got the money back. That was the reason to order at Amazon. Did not have time to install it on this morning. So I could adjust the opening to 8 ° ° clock, I started with the installation of 7 ° ° clock and was a quarter of an hour later completed. It works.
