Only at first glance a rugged phone

The DeTeWe BeeTel 58i ISDN phone made a robust and well-made impression only at first glance. On closer inspection, the appearance of the phone is quite easy. The cheap "plastic design" is particularly noticeable in the keypad.
The features of this phone can hardly be desired. Only the button for switching missing. Relaying a call within a telephone system is a very expensive operation without this key!
To make matters worse, the hands-free phone worked only about 14 days. Then the speaker said no sound and customer support of DeTeWe confirmed the defect of your phone.
Consequence: Exchange of the apparatus against the ISDN phone from another manufacturer.