NO SUPPORTS NEEDED this is a round, smaller (about the same width as the bottle opener itself, the issue with the last one seemed to be that it was to wide) and also more pleasant looking version of my rectangle cap catcher that I made for those bottle openers that mount to a wall and drop the caps, meaning they fall to the floor and are a pain to pick up or are in an annoying place to prevent it falling to the floor (above a table or low down meaning it's "not much further to grab the cap off the floor"). this model comes with a draining hole for all the different liquids that may end up in there whether it's rain, beer, juice of some kind or in some country's, tomato sauce. Simply place 2 screws/nails into wall where you want to mount it under bottle opener. (I place on wall and use a pencil to mark holes) then slide on and push down to secure. When full, slide up and pull out to remove. empty into a bin and slide back on. Happy printing!