+ They work
+ Many choices of sounds
- The melodies are not my cup of tea
- The volume is not adjustable and too loud (especially when you're happy that the baby has just fallen asleep peacefully and then but scare jerky again)
- The supplied batteries were empty after twice use
If you do not need large frills on melodies and can live with a loud ringtone, which is well served by the bell. On the batteries unfortunately seems to be not reliable. We'll see how long I can live with this bell.