Dimensions: approx. 14 cm long. Hidden room dimensions: approx. 8cm x 2.5cm diameter. The default password is iloveU. You can also set your own password. The password between you and your friend cannot be opened when he is wrong. So it's interesting. You can contact us to set your password. The packaging is exquisite, just look at the pictures, I believe you will like it When you open the lock, you see two rings, I'm sure you'll be surprised what you care about. Of course, you can also buy more expensive rings or necklaces. When you set up a new combination, simply turn the screw and reprogram the letter 6 combination ring. Combining mini lock boxes, Christmas and Halloween is the funniest gift for friends, kids and parents. Of course, Valentine's Day is the best gift to give someone.