Our Competitive Advantage MPD-15 Paint Markers are the queen marking pens we trust most. We choose them over other options for their quick-drying formula and long-lasting durability. These markers provide bold, clear markings that stay visible, even through the wear and tear of hive activities. Whether you're marking a queen for easy identification or keeping track of colony progress, these pens offer a reliable, professional solution. Mark your queens according to the last digit of the year she was born using the following color-coding system: Last Digit of the Year Color 6 or 1 White 7 or 2 Yellow 8 or 3 Red 9 or 4 Green 0 or 5 Blue For example: A queen born in 2025 (last digit is 5) would be marked with a blue dot. A queen born in 2024 (last digit is 4) would be marked with a green dot. A queen born in 2023 (last digit is 3) would be marked with a red dot. This color system makes it easy to identify the queen's birth year at a glance!