These are the Cosco "Pullman" Numberers. You will need a separate ink pad for these numberers.
The number before the dash denotes the actual number size (height). The number after the dash denotes number of bands.
A "00" before the dash means the number is slightly bigger than 1/16" high, approximately a size 8 font.
A "0" before the dash means the number is less than 1/8" high, approximately a size 10 font.
A "1" before the dash means the number is 1/8" high, approximately a size 12 font.
A "2" before the dash means the number is 3/16" high, approximately a size 18 font.
A "2.5" before the dash means the number is 1/4" high, approximately a size 24 font.
A "3" before the dash means the number is 5/16" high, approximately a size 30 font.
A "4" before the dash means the number is close to 1/2" high, approximately a size 44 font.
A "5" before the dash means the number is 5/8" high, approximately a size 60 font.