These small door knockers are perfect for internal doors. They are available in many different styles to suit all needs and tastes. The popularity of small door knockers for internal doors can be traced back to the 1930s. These door knockers were available in many shapes with animals and birds being a popular variety. Bedroom door knockers are very similar to front door knockers except that they tend to be smaller in size.  However, these small bedroom door knockers would not look out of place on a small external door.