This is a set of 14 die cut stickers numbered from 1/2 to 7 in 1/2 increments. They can be used to show the volume level on carboys and buckets. These stickers are easy to see because they have white text on a black background plus they are large in size (1.5" x 1.5").
Every carboy is slightly different. You will need to measure out the volume, placing the sticker in the appropriate spot.