Durable materials: The main parts of the keychain are made of acrylic, resistant and durable materials: you can clearly see the inner view after putting in the photo due to light colors on both sides size of the plastic keychains in white: the dimension exterior is approx. 4 x 5.5 cm, the inner dimension is 3.17 x 4.6 cm, suitable for photos of less than 3.17 cm and width less than 4.6 cm wide application: It can be used for business promotions , take school photos and give as a gift, can also be used to leave the phone number to avoid the loss of keys