Miniature Base Size Adapters

Prior to 5e, DND used 44mm or 50mm bases for giants and other large creatures. Today, these are classified as 'huge', and use 75mm bases. A friend introduced me to what was a standard in 4e, large -> huge base adapters made of cardboard, and I decided to make some for my mini collection so I could use older giant minis in my current game.

There are three base adapters:

50mm -> 75mm - Large to Huge adapter
44mm -> 75mm - Large to Huge adapter (old style 'large' size)
25mm -> 50mm