This is the 6 th bell we have tried from different manufacturers. Reach through concrete walls in the basement and first floor was not a problem! Ringtones enough! Has survived the first winter. The first battery replacement is still pending. After failing one of the previous ring. Only criticism: The button on the door must be pressed vigorously to both receivers react. That does not agree towards each postman! So far, I'd buy the bell again and had the 10 euro no regrets more! Therefore, all 5 stars!
