Tecknet wireless doorbell

This is probably the best thing I have ever purchased through Amazon. I live in an apartment and in my bedroom you cannot hear somebody at the door. It was extremely inconvenient when somebody would stop by and I didn't answer the door. Its water proof, so it can be placed outside in the elements. It has different sounds, mine plays 'Green Sleeves'. The best part of all was installation, literally plug it in and it's good to go. Original it has an actual door bell sound but you can easily pick you favorite. And it was $10!