Restorers Victorian 4 Inch Mechanical Twist Doorbell

I bought this doorbell because I remember this type from my childhood. I needed a distinctive and loud doorbell for my old house because I couldn't hear it when someone knocked on my backdoor. I don't have electric doorbells. and the knocker was not loud enough to hear into the living area. This twist doorknob is great. It is loud enough to hear and it delights my grandson to use it when he comes over..